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thesis entitled
THE EFFECTS OF HOCKEY PROTECTIVE EQUIPMENT
ON AEROBIC AND ANAEROBIC PERFORMANCE
presented by

FRED WILLARD BRUNYATE

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Date MAY 19, 1989

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THE EFFECTS OF HOCKEY PROTECTIVE EQUIPMENT

0N AEROBIC AND ANAEROBIC PERFORMANCE

by

Fred Willard Brunyate

A THESIS
Submitted to
Michigan State University

in partial fulfillment of the requirements
for the degree of

MASTER OF ARTS

Department of Health Education,
Counseling Psychology, and Human Performance
College of Education

1989

@00l47Q

ABSTRACT

THE EFFECTS OF HOCKEY PROTECTIVE EQUIPMENT
ON AEROBIC AND ANAEROBIC PERFORMANCE
BY
Fred Willard Brunyate

Ten experienced hockey players age 13 to 15 performed a
maximum aerobic capacity treadmill test and the Wingate
anaerobic capacity test once wearing shorts and once wearing
hockey equipment, except skates. Wearing the equipment
significantly: (a) decreased the subjects' run time, peak
power, and mean power, (b) increased the heart rate at one
exercise level, two rest periods, and after five minutes of
recovery, (c) increased the ventilation and absolute oxygen
consumption at three levels of submaximal exercise and three
rest periods, and (d) increased the blood lactate
concentration following two levels of exercise. No
significant differences were found in oxygen uptake relative
to total test weight, maximum oxygen uptake, peak lactate
concentration, lactate concentration after the Wingate test,
blood pressure, oxygen consumption during recovery, and
lactate concentration during recovery. The significant
changes observed are attributed to the excess weight of the

equipment, particularly that on the legs.

ACKNOWLEDGEMENTS

I’d like to thank Dr. Ken Stephens, for talking me into
starting this, Dr. Wayne VanHuss, for encouraging me to
finish it, and Dr. Kwok-Wai Ho, the third member of my
thesis committee.

I’d like to thank Ted Kurowski and his crew of experts
for the many hours of tests they administered on my behalf.

I'd like to thank the young hockey players who
willingly ran themselves to exhaustion for this study.

I’d like to thank Lyle Miller, my employer, for his
patience while I juggled work and school.

And, I’d like to thank my parents for their faith and

support while they waited for me to finish.

iii

List of
Chapter
Chapter
Chapter
Chapter
Chapter

List of

TABLE OF CONTENTS

Tables

I - The Problem

II - Related Literature

III - Research Methods

IV - Results and Discussion

V - Conclusions and Recommendations

References

iv

17

22

46

51

Table 1:

Table 2:

Table 3:

Table 4:

Table 5:

Table 6:

Table 7:

Table 8:

Table 9:

Table 10:

Table 11:

LIST OF TABLES

Physical Characteristics

Pre—Test Heart Rate, Blood Pressure,
and Blood Lactate Concentration

Maximum Aerobic Characteristics

Heart Rate and Blood Pressure During
Exercise

Heart Rate and Blood Pressure in Rest
and Recovery

Ventilation and Oxygen Uptake During
Submaximal Exercise

Total Oxygen Uptake During Rest and
Recovery

Blood Lactate Concentration

Blood Lactate Concentration Recovery
Percentage

Anaerobic Characteristics

Summary of Research Hypotheses
and Judgements

23

25

26

28

30

33

37

40

42

43

45

Chapter I - The Problem

Over the past decades, protective equipment for ice
hockey players has undergone an evolution in design. A
greater awareness of the injuries of the game led initially
to development of improved head and face protection (Love,
1963, Pashby, et al, 1975). As the game changed to include
more checking by bigger and faster players, the
manufacturers strengthened other equipment as well. For
example, the elbow pads were lengthened to cover the full
gap between the gloves and the shoulder pads. The
perfunctory chest protection of the shoulder pads was
thickened and extended downwards. More recently, the
distinctive baggy short pants are being replaced by a close
fitting girdle of space age padding (Kalchman, 1981).

Appropriately, it is the youth hockey players who are
among the best protected. The Amateur Hockey Association of
the United States (AHAUS) now requires that each player wear
a helmet and full face mask approved by the AHAUS Hockey
Equipment Certification Council (HECC) (AHAUS, 1983). The
Canadian Amateur Hockey Association has similar
requirements.

In addition to helmet and face mask, the well-dressed
youth hockey player wears shoulder pads, elbow pads, gloves,

cup, pants or girdle, shinpads, and a mouthguard. The total

2
weight can easily exceed four kilograms for older players,

without including the player’s skates and stick.

Excess weight has been shown to interfere with skating
(Montgomery, 1981) and running (e.g., Cureton, et al, 1978)
performance. Weight carried artificially above the legs can
be considered the same as natural obesity (Goldman and
Iampietro, 1962), while weight added to the feet or legs
incurs a greater increase in energy cost due to the
additional movement of the weight during running and walking
(Soule and Goldman, 1969).

Maximum oxygen uptake values found by Ferguson,
Marcotte, and Montpettit (1969) in an on-ice skating test
are comparable to values found in treadmill tests. Treadmill
running appears to be a reasonable approximation of skating
for determining maximal aerobic capacity.

Bouchard, Taylor, and Dulac (1982) indicate that
laboratory measures of anaerobic capacity correlate well
(r=-.74) with at least one running field test. Considering
the similarities in stroke between cycling and skating, the
Wingate cycling test of anaerobic capacity (Bar-Or, Dotan,
and Inbar, 1977) is assumed here to provide a reasonable
approximation of skating anaerobic capacity. However, since
cycling is not a weight bearing activity, as is skating, the
approximation may not be as close as the one mentioned above
for aerobic capacity.

Hockey players require both aerobic and anaerobic

conditioning. During a game, a player typically will play in

3
shifts of thirty to ninety seconds with a rest interval

between shifts of one to three times that, depending on the
number of players on the team, the coach's philosophy, and
the game situation. Many youth hockey teams, particularly in
the younger age groups, select only enough players to have
two lines who alternate shifts.

During a shift, a player may perform brief bursts of
acceleration, 60 yard dashes, or fairly continuous skating,
interspersed with coasting, easy skating, or standing still.
Sound anaerobic conditioning is crucial to the player's
tactical play during a shift, while his aerobic training
allows him to maintain peak performance throughout the game.

This study will use treadmill running and stationary
cycling to examine the aerobic and anaerobic capacities of
elite youth hockey players, and the effects of wearing their
protective equipment on their performance on these

laboratory tests.

Need for the Study

This study seeks to determine if there are significant
detrimental effects of hockey protective equipment on
aerobic and anaerobic performance in a laboratory situation.
The areas in which performance may be affected may deserve
further study either in on-ice tests or in new designs in

the equipment worn during the tests.

Purpose of the Study

The study will examine the performance of experienced
youth hockey players on an aerobic treadmill test and an
anaerobic cycling test. The players will be tested once
dressed in running shorts and once dressed in full hockey
protective equipment, though without skates. The study was
designed to look at the effects of the equipment on oxygen
uptake, blood lactate concentration, heart rate and blood
pressure during primarily aerobic exercise, and on blood
lactate concentration and power output during primarily

anaerobic exercise.

Research Hypotheses

The research hypotheses are that performing the tests
while wearing hockey protective equipment will:

a) decrease the total run time,

b) increase the heart rate and blood pressure during
exercise, rest, and recovery,

c) decrease the peak heart rate,

d) increase the ventilation and oxygen uptake relative
to body weight at each level of submaximal exercise, but
show no change relative to the total test weight,

e) decrease the maximum oxygen consumption relative to

body weight,

5
f) increase the oxygen consumption during the 1.5

minute rest period following each level of exercise, and the
oxygen consumption for five and ten minutes following
exercise,

g) increase the blood lactate concentration at each
level of exercise,

h) decrease the peak blood lactate concentration,

1) decrease the percent recovery of blood lactate
concentration at 5, 10, and 60 minutes following exercise,
j) show no decrease in anaerobic peak power, mean

power, and percent of peak power produced after thirty
seconds, and
k) show no increase in the blood lactate concentration

following anaerobic exercise.

Research Plan

The Michigan State University Center fo the Study of
Human Performance has developed a treadmill test protocol
involving alternating periods of exercise at increasing
intensity and rest. Oxygen uptake and ventilation data are
recorded using a gas bag system, while the rest periods
provide opportunities to obtain blood samples and blood
pressure readings. For a representative study, see VanHuss,
Stephens, Vogel, et a1, 1986.

The Wingate Bicycle Test is a frequently used test of
anaerobic capacity (Bar-Or, Dotan, and Inbar, 1977). The

test records the total work output of the subject over

6
thirty seconds and the peak power in a five second segment.

Blood samples for lactate concentration are taken before and

after the test.

Delimitations

Wearing uniforms or protective equipment when working
or exercising involves thermal effects on the wearer
(Duncan, Gardner, and Barnard, 1979: Fox, et al, 1966:
Mathews, Fox, and Tanzi, 1969). Since it is not possible to
reproduce in this laboratory the usual environment of an
active ice hockey player, the thermal effects are beyond the

scope of this study.

Limitations

The results of this study are limited in application to
experienced youth hockey players age 13 to 15. They are
further limited to the laboratory setting of an aerobic

treadmill test and an anaerobic bicycle test.

Chapter II - Related Literature

The available literature on the effects of protective
equipment on athletic performance is very limited, with the
exception of running shoe design. Most of the information
reviewed here covers the effects of excess weight in
general, with the more specific equipment studies grouped at
the end. The majority of the literature is concerned with
aerobic capacity and heart rate. Very little data have been

reported on effects on anaerobic capacity.

Excess Weight - Obesity

The following two studies investigated the relationship
between obesity and oxygen uptake, one by weight reduction
and one by induced weight gain.

Sprynarova and Parizkova (1965) tested seven obese
boys, with an average age of 11.5 years, before and after
the boys attended a weight loss camp. In each test, the boys
ran a progressive maximal treadmill test. During the weight
loss camp, the boys lost an average of 14% of their post-
camp body weight. The loss of the excess weight
significantly (p<.01) increased their treadmill run time.
During the second test, the absolute oxygen consumption was
lower than the pre-camp test level at every speed. The

maximum absolute oxygen consumption increased significantly,

 

8
but both the increase per unit of body weight and the

decrease per unit of lean body mass were not significant.
The correlation between body weight and absolute oxygen
uptake increased from r=0.75 to r=0.93 when the subjects
lost weight.

In the second study, Hanson (1973) had four twenty-five
year old subjects alter their diet to produce an average 19%
weight gain. The subjects were tested on a treadmill
(walking at three grades) and on a bicycle ergometer (at
three loads) prior to the weight gain, after an average 15%
weight gain, after the average 19% gain, and five months
later after the loss of most of the gained weight, but with
a backpack load used to return each subject's total weight
to that of the third test. Significant changes (p<.05) were
observed in ventilation and absolute oxygen uptake at the
higher grades of the treadmill test, with increases
occurring at all levels. The percentage increases in oxygen
consumption were approximately the same as the corresponding
percentage increase in weight gain. Tests when carrying the
backpack on the treadmill showed no significant differences
from tests with the natural weight. The subjects showed no
increase in the energy cost of bicycle ergometry due to the
increase in body weight. The authors point out that

stationary cycling is not a weight bearing activity.

9
Excess Weight - Carried Weight

Goldman and Iampietro (1962) studied the energy cost of
walking on a treadmill with three standard backpack loads of
10, 20, and 30 kilograms. Five men, average age 22, were
tested at each of 22 combinations of load, grade (3%, 6%,
and 9%), and speed (1.5, 2.5, 3.5, and 4.0 mph). For each
combination of speed and grade, the energy cost, in
kilocalories per kilogram of body weight per minute, clearly
increases with each increase in load. When the energy cost
is computed per kilogram of total weight (body weight plus
load), it is virtually constant for each combination of
speed and grade. The authors concluded that the energy cost
of walking is independent of what portion of the weight is
body weight and what portion in a backpack.

Soule and Goldman (1969) investigated the effects of
carrying excess weight on the head or hands. In separate
tests, the ten male subjects, average age 22, carried no
weight, 4 kg on each hand, 7 kg on each hand, and 14 kg on
their heads at speeds of 4.0, 4.8, and 5.6 kph. the authors
found only slight increases in energy cost over the value
expected if the load was carried in a backpack. They
suggested some or all of the additional energy cost arises
from efforts to stabilize the load, particularly that on the
head.

Cureton, Sparling, Evans, et a1, (1978) examined the
effects of excess weight on aerobic capacity and distance

running performance. Six trained runners (four male, two

10
female, ages 20 to 30) performed a maximal, multi-stage,

progressive treadmill test and a twelve minute run four
times over a four week period with no added weight or 5, 10,
or 15 percent of their body weight carried on a harness
around the waist and shoulders. The authors found highly
significant (p<.01) decreases in the distance run during
twelve minutes and the time run on the treadmill, and in
maximum oxygen uptake per unit of total weight (body weight
plus weight carried). No significant differences were found
in ventilation, oxygen uptake per unit of body weight or
lean body mass, or heart rate during the maximal stress
test. The authors also investigated the energy cost of
running during submaximal exercise. At seven miles per hour,
significant (p<.05 or less) changes occurred in ventilation,
heart rate, and oxygen uptake per unit of body weight and
per unit of lean body mass, while changes in oxygen uptake
per unit of total weight were not significant. They
concluded that the effects of the additional weight are due
almost entirely to the increased energy cost of submaximal
exercise.

Cureton and Sparling (1980) used a harness to add
weight to ten male subjects, average age 26, to equate their
excess weight (added weight plus body fat) to that of
arbitrarily paired female subjects. Again, the added weight
significantly (p<.05) reduced the males' treadmill run time
and twelve minute run performance. At a submaximal work

rate, the added weight increased the heart rate and oxygen

11
uptake, both absolute and per unit of lean body mass, while

decreasing the oxygen uptake per unit of total weight. On
the maximal treadmill run, the added weight decreased their
oxygen uptake per unit of total weight and the respiratory
quotient, but did not significantly affect the other

measures .

Excess Weight - Weight on Feet

Soule and Goldman (1969), cited earlier, included the
additional condition of a load of 6 kilograms on each foot
'in the form of double wall boots filled with mercury. In
this case, the increased energy cost over the no load
condition was significant (p<.01) and the increased cost
with each increase in speed was highly significant (p<.001).
The authors suggest some of the increase in energy cost is
due the reduced mobility of the ankle joint from the heavy
boots, but the major part of the increase comes from the
effort of moving those weights with each step.

Catlin and Dressendorfer (1979) considered the effect
of shoe weight on running energy costs of seven marathoners.
The heavier training shoe (0.87 kg) increased the energy
cost of running 0.51 kilocalories per minute over running
with a racing shoe (0.52 kg) (p<.05).

Jones, et a1, (1984) investigated the effects of
walking (at 2.5, 3.5, and 4.5 mph) and running (at 5.5, 6.5,
and 7.5 mph) in shoes, boots, and shoes plus weight added to

equal the weight of the boots. The subjects' shoes had an

12
average weight of 0.6 kilograms and the boots 1.8 kilograms.

The maximum oxygen uptake for each subject, wearing shoes,
had been obtained in a previous test. The subjects were six
trained and eight untrained males with an average age of 30.
The oxygen consumption when wearing boots instead of shoes
was significantly higher (p<.05) at all speeds except the
lowest. The increase averaged 8%, while the boots increased
each subject’s weight by an average of only 1.4%. The
subjects' heart rate was higher, though not significantly,
when wearing boots instead shoes. Oxygen consumption when
wearing shoes plus the added weight was significantly higher
(p<.05) at the three running speeds. When compared to the
boots, weight by itself accounted for up to 70% of the

difference between shoes and boots.

Excess Weight - Skating

Montgomery (1981) investigated the effects of excess
weight on the mostly anaerobic task of six repetitions of
skating 100 yards. A repetition was started every thirty
seconds. The subjects were twelve males with an average age
of 21. Each carried, during separate tests over a two week
period, no excess weight, and 5, 10, and 15 percent of their
body weight in a vest. The results showed a significant
(p<.05) decrease in speed and increase in both total
performance time and the drop-off index, an indicator of
anaerobic endurance. There were no significant effects on

heart rate after three and five minutes of recovery.

13

Excess Weight - Uniforms

Duncan, Gardner, and Barnard (1979) studied eleven
firefighters, average age 29, in street clothes and
protective uniforms at submaximal work rates on a treadmill.
The uniforms, including rubber lined clothes, boots, and
breathing apparatus, added an average of 21.82 kilograms to
each subject's total weight. The subjects walked on a
treadmill at four kilometers per hour and ten percent grade
for fifteen minutes. Heart rate, oxygen uptake, and
breathing rate were measured for every fifth minute of
exercise, and heart rate at each minute of recovery. The
mean heart rate of uniformed subjects showed significant
(p<.01) increases at all points, including recovery. The
average oxygen consumption and breathing rate after fifteen
minutes of exercise both increased significantly (p<.01).

Fox and Mathews at Ohio State University conducted two
studies investigating the causes of heatstroke deaths in
football players. In the first (Fox, Mathews, Kaufman, et
a1, 1966), five high school players ran on a treadmill at
six miles per hour for twenty minutes dressed in a hospital
scrub suit and their football uniform. Heart rates were
recorded for twenty minutes of exercise and thirty minutes
of recovery. Ventilation and oxygen consumption were
recorded every fifth minute of exercise. The mean heart rate
increased steadily, with a significant difference of fifteen

beats per minute at the end of exercise (p<.01), uniform

14
over scrub suit. The difference remained throughout the half

hour recovery and was still significant (p<.05) at the end.
There was no difference in the heart rate per kilogram of
total weight during exercise. Oxygen consumption was
reported per kilogram of total weight, including the average
14.7 pounds of football uniform. No differences were
reported in oxygen consumption (ml/kg/min), total
ventilation (ml/kg/min), ventilation equivalent, or oxygen
pulse (ml/min/beat). However, the authors mention, without
reporting significance, that, in uniform, oxygen
consumption, ventilation, and heart rate increased when the
weight carried was not included in the calculation. The
authors attribute the reported changes to the weight and
thermal effects of the football equipment. They also
reported significant differences in core temperature
elevation during exercise and temperature after thirty
minutes of recovery.

Mathews, Fox, and Tanzi (1969) continued this line of
investigation with nine male graduate students running on a
treadmill (9.6 km/hr, 0% grade) in shorts, football uniform,
and shorts plus a backpack weighing the same as the football
uniform (6.2 kg). Besides extensive data on skin and rectal
temperature, they recorded heart rate, ventilation, and
oxygen consumption every fifth minute for thirty minutes of
exercise. This paper provided little useful analysis of the
oxygen consumption and ventilation data: the authors’

interest was in the temperatures. Average oxygen consumption

15
was consistently higher with the backpack than with either

shorts or uniform, and higher with the uniform than the
shorts, though apparently not significantly. The authors
suggest the energy cost is greater for a concentrated weight
than for the same weight distributed evenly over the body.
At the end of recovery, the oxygen consumption was still
significantly increased over the pre-exercise levels, with
the mean difference for the uniform trial (p<.02) about
twice that of the other two (p<.05 for shorts, p<.10 for
backpack). Ventilation increased during exercise for all
three tests, with the uniform and backpack conditions
noticeably above the shorts-only condition at each point (no
significance was mentioned). The only significant difference
between pre-exercise and end of recovery ventilation
occurred with the uniform on (p<.05). The heart rate
increased faster and longer during exercise with a backpack
or uniform than with shorts, and remained similarly elevated

throughout recovery.

Summary

Excess weight seems to have the same effects on aerobic
performance whether it is natural obesity or artificially
added. There are some additional energy costs associated
with stabilizing heavy concentrated loads on one part of the
body. At submaximal exercise levels, the weighted performer
operates at a higher percentage of his maximum heart rate

and oxygen consumption. Peak capacity is reached more

16
quickly, decreasing the duration of the performance. Excess

weight carried on the feet has effects out of proportion to
the weight carried due to the extra movement of the weight
required.

Added weight shows no effect on anaerobic power or
capacity as measured by a stationary bicycle test, but does
decrease performance in the weight-bearing activity of
skating. Uniforms and protective clothing also have thermal

effects on the wearer during exercise.

 

17

Chapter III - Research Methods

Subjects and Sample

The ten subjects were volunteers from the sixteen
players of the Bantam AA youth hockey team of the Greater
Lansing Amateur Hockey Association. Eight turned fourteen
during 1984: two were one year younger. All were experienced
hockey players. The team had won the Michigan State
Championship in its class. The team continued its normal
training through the National Tournament. The testing
sessions were scheduled for the two weekends immediately
following the tournament, while the players were still at or
near peak condition.

Each subject was assigned randomly to a starting time
to be used for both test sessions. Although each subject was
at the laboratory for about two hours, the starting times
were about forty five minutes apart. The subjects further
were divided randomly into two groups. One group tested
first in full hockey equipment, except skates and stick, and
second in running shorts. The other half tested first in
shorts and second in equipment to control the effects of
familiarization with the testing and any detraining that
might occur. Samples of the test schedule and other
descriptive items that were presented to the subjects are

located in Appendix A.

18

Test Protocols

Each subject performed an intermittent maximal aerobic
capacity treadmill test and the Wingate anaerobic capacity
bicycle test once in shorts and once in hockey equipment.
During one test session, the subject's percentage of body
fat was determined by hydrostatic weighing.

On arrival at the laboratory, each subject was weighed
wearing shorts only. Electrodes were attached for the three-
lead electrocardiogram (CM-5), and the subject sent to dress
for running. Those wearing their hockey equipment were
instructed to dress as they would for a game, including a
game jersey. The subject was weighed again to determine the
weight of the equipment. The equipment was dry before the
test began. The shinpads were weighed separately before the
subject dressed. Pre-exercise heart rate and blood pressure
were taken, as was a blood sample, from a finger tip, for
blood lactate concentration analysis.

The treadmill run consisted of alternating three-minute
runs and minute-and-a-half rest periods, repeated to
exhaustion and followed by a ten-minute recovery period. The
initial exercise level was at six miles per hour and zero
percent grade. The second exercise level was at six miles
per hour and five percent grade. Each subsequent exercise
level was at an increase of one mile per hour and one
percent grade. During rest and recovery, the subject sat on

a table placed over the treadmill.

19
Expired air was collected in a Douglas bag system for

each minute of exercise and each half-minute of rest. During
recovery, expired air was collected in five one-minute bags,
one two-minute bag, and one three-minute bag. The subject's
heart rate was recorded at the end of each bag time.
Immediately after each exercise level and at five and ten
minutes of recovery, the subject's blood pressure was
recorded and a finger tip blood sample was taken. Additional
blood samples were taken after fifteen and sixty minutes of
recovery. The subjects were free to move about the room
during the forty five minutes before the final blood sample.
The Wingate bicycle test was administered immediately
after the sixty minute blood sample was taken. The subject
rode for eight seconds at the highest rpm he could manage to
determine his maximum anaerobic power for five seconds.
After a two minute rest, the subject pedaled at his maximum
rpm for thirty seconds. The pedal revolutions were recorded
on a chart recorder. The test load was 0.045 kilograms per
kilogram of body weight, rounded to the nearest half
kilogram, and was the same for both tests. A blood sample

was taken after one minute of seated rest.

Dependent Variables Collected

The following dependent variables were collected during
the treadmill run:

a) pre-exercise heart rate and heart rate during

exercise, rest, and recovery,

20
b) pre-exercise blood pressure, blood pressure

following each level of exercise, and blood pressure during
recovery,

0) blood lactate concentration before exercise,
following each level of exercise, and during recovery,

d) ventilation and percentage of oxygen and carbon
dioxide in the expired air during exercise, rest, and
recovery, and

e) total running time.

The following dependent variables were computed from
data collected during the treadmill run:

f) oxygen consumption in both liters per minute and
milliliters per kilogram per minute during exercise, rest,
and recovery, and

9) percent recovery of blood lactate concentration at
five, ten, fifteen, and sixty minutes of recovery.

The following dependent variables were collected during
the Wingate anaerobic test:

h) blood lactate concentration after the test, and

i) pedal revolutions for the last five seconds of the
eight-second test and each five seconds of the thirty-second
test.

The following dependent variables were computed from
the data collected during the Wingate test:

j) peak power during any five second segment of either

test,

21
k) mean power all six segments of the thirty second

test, and
1) percent drop-off from the first to last segments of

the thirty second test.

Statistical Analysis

The statistical analysis of the data utilized one-tail
t-tests of the significance of the difference between the
means of two normal dependent samples. The variables being
tested were assumed to be normally distributed for the
population of experienced Bantam youth hockey players.
Nothing was known, or required to be known, about the
variance of the population or samples.

Alpha was set at 0.05 and beta at 0.20. A difference of
one-half of a standard deviation was to be considered
significant. The necessary and sufficient sample size was
51. Due to financial and time limitations, it was not

possible to test that many subjects at this time.

22

Chapter IV - Results and Discussion

The use of a maximum aerobic capacity treadmill test
and the Wingate anaerobic capacity bicycle test proved
satisfactory for determining changes in the subjects'
performances caused by their wearing hockey protective
equipment. The test sessions proceeded as planned. All
subjects completed the test sequences without incident. The
results of the test sessions are presented in Tables 2
through 10. Column A in each pair of columns contains the
data from the subjects’ tests with their hockey equipment,
the experimental condition. Column B contains the data from
the standard tests in running shorts, the control condition.

The results are presented below and discussed in
relation to the expected increases in heart rate, blood
pressure, ventilation, oxygen consumption, and blood lactate
concentration for submaximal exercise and corresponding

decreases for the subjects' maximum performance.

Initial Conditions

Table 1 presents the ten subjects’ initial conditions.
The weight of each subject’s hockey equipment is listed as a
percentage of the his body weight, and the weight of his
shinpads as a percentage of his total equipment weight. Each

player's equipment weighs from 8 to 12 percent of his body

23
Table 1: Physical Characteristics

Subject Age Height Weight % Fat
(Yr) (cm) (kg)

1 15.1 180 68.2 12.1

2 14.8 188 75.3 9.3

3 14.1 163 51.2 16.9

4 14.9 180 63.5 12.6

5 15.2 182 66.9 5.6

6 14.5 167 57.9 17.4

7 14.3 157 48.0 15.5

8 13.5 160 48.7 17.6

9 13.9 160 47.9 19.0

10 15.3 168 57.6 13.4
Mean 15.3 168 48.0 8.2
(s.d.) 0.6) ( 11) (10.3) 4.6)
Subject Eqp Wt % BW SP Wt % EQP Wt

(M) (1“!)

1 5.5 8.1 .76 13.8

2 6.2 8.2 .72 11.6

3 5.0 9.8 .74 14.8

4 7.7 12.1 1.04 13.5

5 6.4 9.6 .64 10.0

6 6.1 10.5 .84 13.8

7 5.6 11.7 1.04 18.6

8 4.6 9.4 .60 13.0

9 3.9 8.1 .64 16.4

10 3.8 7.9 .76 20.0
Mean 3.8 9.5 .78 14.6
(s.d.) (1.2) (1.5 (.16) 3.0)

24
weight, with the shin pads accounting for 10 to 20 percent

of that weight.

There were no significant differences in the pre-test
measures of heart rate, blood pressure, and blood lactate
concentration, as shown in Table 2. These t-tests were done
as two—tail tests since there was no reason to expect a
difference in a specific direction. The blood lactate
concentration was nearly significant, although there is no
known reason why this should be so. Seven of the subjects
had higher lactate concentrations prior to testing without
their hockey equipment and two registered higher prior to
testing with their equipment. One subject had the same
concentration both days. Possibly the subjects were more

active on the days they did not wear their equipment.

Maximum Aerobic Capacity Characteristics

Wearing their hockey equipment significantly decreased
the subjects’ mean total run time over 22 percent (Table 3).
Seven of them ran into Level 4 (minutes 10, 11, and 12),
while three could manage only Level 3. Without their
equipment, six subjects ran into Level 5: four into Level 4.
Two subjects were in the lower level for both tests. There
was a significant decrease in the peak heart rate. However,
the difference was less than half a standard deviation. The
difference also was close to the limit of resolution of the
heart rate monitoring device at high heart rates. The

decrease may be significant but not relevant. There were no

25

Table 2: Pre-Test Heart Rate, Blood Pressure,
and Blood Lactate Concentration

Heart Rate Systolic B.P.
_ (bpm) (mqu)
Subject A
1 63 72 112 122
2 75 72 138 130
3 72 88 128 124
4 87 75 120 120
5 66 71 108 122
6 88 84 108 118
7 96 80 116 110
8 107 95 112 110
9 85 96 108 112
10 97 63 118 118
Mean 84 80 117 119
(s.d.) (14) (11) ( 10) ( 6)
N T P Value
Pre-Test Heart Rate 10 0.84 0.42
Pre-Test Systolic B.P. 10 -0.76 0.46
Diastolic B.P. Blood Lactate
, (mmng) (mmol/l)
Subject A B
1 72 68 1.65 1.65
2 70 65 1.80 3.00
3 82 60 2.70 2.30
4 80 90 2.05 1.70
5 76 78 1.60 2.05
6 80 78 1.55 1.80
7 70 72 1.40 1.85
8 74 72 1.45 2.10
9 68 62 1.10 1.85
10 62 60 1.95 2.30
Mean 74 71 1.73 2.06
(s.d.) ( 6) (10) ( .44) ( .40)
N T P Value
Pre-Test Diastolic B.P. 10 1.13 0.29
Pre-Test Lactate Gone. 10 -2.15 0.06
Significance: * p<.05: ** p<.01

26
Table 3: Maximum Aerobic Characteristics

Total Run Time Maximum VO

(mm:ss) (ml/kg/min
Subject A B A B
1 10:00 11:31 57.6 55.2
2 11:00 13:17 60.2 59.0
3 9:56 10:42 60.8 59.4
4 10:02 13:10 57.9 61.0
5 11:30 13:53 56.1 60.2
6 7:57 11:00 52.5 57.5
7 7:12 10:37 52.0 54.0
8 9:36 13:00 62.1 59.3
9 8:44 12:53 59.6 58.5
10 9:55 13:28 58.9 62.3
Mean 9:35 12:21 57.8 58.7
(s.d.) (1:18) (1:15) ( 3.4) ( 2.5)
N T P Value
Total Run Time 10 -8.51 0.00 **
Maximum V02 10 -0.94 0.19

Peak Heart Rate Peak Lactate

(mm:ss) (ml/kg/min)
Subject A B A B
1 206 203 10.20 11.95
2 183 200 12.95 14.50
3 207 204 12.15 9.65
4 200 210 13.75 12.75
5 210 209 18.30 15.15
6 210 210 10.60 10.80
7 210 210 10.80 11.85
8 220 240 9.20 12.65
9 230 240 11.10 18.55
10 205 210 9.85 13.25
Mean 208 213 11.89 13.11
(s.d.) ( 12) ( 14) ( 2.66) ( 2.50)
N T P Value
Peak Heart Rate 10 -2.08 0.03 *
Peak Lactate 10 -1.23 0.12
Significance: * p<.05; ** p<.01

27
significant decrease in maximum oxygen uptake relative to

body weight or peak lactate concentration.

Heart Rate

The maximum heart rate during each level of exercise
showed no major changes due to the hockey equipment (Table
4). While statistically significant at Level 2, the
difference was less than one half of one standard deviation.
Since the other levels showed heart rates with no
significant differences, this result may be anomalous. A
larger sample size would be needed to resolve this question.

The minimum heart rate during each rest period showed
greater effects of the hockey equipment (Table 5). The
difference was significant following the first and second
exercise levels. Occasional difficulties with the heart rate
monitor and three subjects who could not complete Level 3
when wearing equipment reduced the sample size for Levels 1
and 3. Following exercise, the heart rate may recover less
quickly when wearing the hockey equipment. There was a
substantial amount of extra oxygen consumed during each of
the three rest periods (Table 6). The increased heart rate
would be involved in mobilizing this extra oxygen to
replenish the muscles.

There does not appear to be any difference in heart
rate immediately following the subjects' maximal efforts.
The heart rate was significantly elevated after five minutes

of recovery and nearly so after ten minutes. These elevated

28
Table 4: Heart Rate and Blood Pressure During Exercise

Level 1: Heart Rate Systolic BP Diastolic BP
(bpm) (10111119) (111111119)
Subject A B A B A B
1 162 145 170 168 72 70
2 132 154 180 180 72 90
3 178 178 182 174 86 80
4 168 170 188 192 90 80
5 164 160 162 170 76 75
6 190 178 172 162 90 90
7 197 175 152 150 76 80
8 200 195 144 152 82 72
9 205 195 180 168 80 78
10 175 160 182 160 82 74
Mean 177 171 171 168 81 79
(S-d-) ( 22) ( 17) ( 14) ( 13) ( 7) ( 7)
N T P Value
Level 1 Heart Rate 10 1.55 0.08
Systolic Blood Pressure 10 1.20 0.13
Diastolic Blood Pressure 10 0.65 0.27
Level 2: Heart Rate Systolic BP Diastolic BP
(hp!!!) (11110119) (mmHg)
Subject A B A B A B
1 188 176 198 194 76 70
2 172 176 198 192 80 85
3 195 185 190 190 88 70
4 190 192 188 190 80 70
5 183 177 164 170 70 65
6 205 205 162 180 80 90
7 205 205 * 158 * 82
8 210 204 152 166 88 78
9 210 207 182 192 80 78
10 200 185 208 158 92 80
Mean 196 191 182 179 82 77
(S-d-) ( 13) ( 13) ( 19) ( 15) ( 7) ( 8)
N T P Value
Level 2 Heart Rate 10 2.31 0.02 *
Systolic Blood Pressure 9 0.17 0.44
Diastolic Blood Pressure 9 1.84 0.05

Significance: * p<.05: ** p<.01

29
Table 4: (continued)

Level 3: Heart Rate Systolic BP Diastolic BP
(bpm) (mmHg) (mmHg)
Subject A B A B A B
1 205 192 208 190 80 70
2 183 186 192 190 80 90
3 204 193 198 198 90 80
4 200 201 170 178 80 80
5 205 205 166 200 80 70
6 210 205 158 182 85 82
7 205 210 152 170 70 90
8 215 215 160 172 98 78
9 230 230 170 198 84 80
10 205 200 210 172 92 90
Mean 206 204 178 185 84 81
(s.d.) ( 12) ( 13) ( 22) ( 12) ( 8) ( 7)
N T P Value
Level 3 Heart Rate 10 1.34 0.11
Systolic Blood Pressure 10 -0.95 0.82
Diastolic Blood Pressure 10 0.81 0.22
Level 4: Heart Rate Systolic BP Diastolic BP
(bpm) (mmHg) (mmHg)
Subject A B A B A
1 206 199 210 188 88 68
2 169 195 168 185 70 80
3 207 204 180 200 82 74
4 190 210 142 185 60 65
5 210 205 132 170 70 60
6 * 210 * 170 * 78
7 * 210 * 148 * 70
8 220 240 160 158 90 92
9 * 230 * 182 * 80
10 205 210 204 168 92 80
Mean 201 211 171 175 79 75
(s.d.) ( 17) ( 14) ( 29) ( 15) (12) ( 9)
N T P Value

Level 4 Heart Rate 7 -1.54 0.91
Systolic Blood Pressure 7 -0.74 0.76
Diastolic Blood Pressure 7 1.17 0.14

Significance: * p<.05; ** p<.01

30

Table 5: Heart Rate and Blood Pressure in Rest and Recovery

Rest 1 HR
(bpm)

Subject A B
1 86 77

2 98 108

3 118 116

4 108 100

5 107 95

6 139 130

7 139 125

8 128 *

9 150 *

10 * 87
Mean 119 105
(s.d.) ( 21) ( 18)

Rest Period 1 Heart Rate
Rest Period 2 Heart Rate
Rest Period 3 Heart Rate

Rec.+1 HR
(bpm)

Subject A B
1 132 160

2 163 155

3 170 163

4 143 142

5 160 168

6 180 177

7 170 160

8 170 180

9 175 197

10 140 168
Mean 160 167
(s.d.) ( 16) ( 15)

Recovery + 1 Min. Heart Rate
Recovery + 2 Min. Heart Rate
Recovery + 3 Min. Heart Rate

Significance:

Rest 2 HR
(bpm)

A B
113 87
122 123
148 125
122 111
127 118
150 130
160 135
150 153
175 147
147 90
141 122

( 20) ( 22
N
7
10
5
Rec.+2 HR
(bpm)

A B
119 112
129 127
145 137
120 124
147 139
145 153
141 135
145 151
160 170
132 138
138 139

( 13) ( 16
N
10
10
10

* p<.

)

2.05
3.58
1.10

)

T

-1.42
-0.13
0.74

Rest 3 HR
(bpm)

A B
129 130
145 130
164 140
130 134
140 143

* 129

* 150
155 *

* 173

* 135
144 140

( 14) ( 14)
P Value
0.04 *
0.00 **
0.17
Rec.+3 HR
(bpm)
112 110
120 115
132 126
118 114
133 130
139 138
137 120
135 147
148 160
124 118
130 128
( 11) ( 16)
P Value
0.91
0.55
0.24

05; ** p<.01

31
Table 5: (continued)

Rec.+4 HR Rec.+5 HR Rec.+10 HR
, (bpm) (bpm) (bpm)
Subject A B A B A
1 113 112 113 108 114 112
2 116 113 117 116 111 112
3 126 124 126 129 129 123
4 117 115 120 115 130 118
5 127 119 125 125 126 113
6 137 122 131 117 132 122
7 129 120 135 122 139 120
8 135 147 140 135 135 139
9 145 151 148 150 140 149
10 131 120 128 128 139 138
Mean 128 124 128 125 130 125
(s.d.) ( 10) ( 14) ( 11) ( 12) ( 10) ( 13)
N T P Value
Recovery + 4 Min. Heart Rate 10 1.30 0.11
Recovery + 5 Min. Heart Rate 10 2.05 0.03 *
Recovery +10 Min. Heart Rate 10 1.79 0.05
Rec.+5 SBP Rec.+5 DBP
(mmHg) (mmHg)
Subject B A
1 142 124 80 60
2 140 130 72 70
3 142 148 80 70
4 118 135 68 60
5 128 135 70 60
6 128 132 82 64
7 132 117 64 64
8 124 142 84 72
9 132 158 66 78
10 152 136 78 82
Mean 134 136 74 68
(S-d-) ( 10) ( 12) ( 7) ( 8)
N T P Value
Rec. + 5 Min. Systolic BP 10 -0.38 0.64
Rec. + 5 Min. Diastolic BP 10 2.04 0.03 *

Significance: * p<.05; ** p<.01

32
Table 5: (continued)

Rec.+5 SBP Rec.+5 DBP
(mmHg) (mmHg)
Subject A B A B
1 135 118 80 60
2 108 110 62 75
3 128 128 80 68
4 100 120 60 75
5 94 120 60 65
6 120 128 80 70
7 128 118 70 64
8 118 110 78 76
9 128 122 74 76
10 140 115 90 78
Mean 120 119 73 71
(S-d-) ( 15) ( 6) (10) ( 6)
N T P Value
Rec. + 10 Min. Systolic BP 10 0.20 0.42
Rec. + 10 Min. Diastolic BP 10 0.75 0.24

Significance: * p<.05: ** p<.01

Level 1: Ventilation

Subject

ODQQO‘U‘I-FUNH

I-'

Mean
(s.d.)

33

Table 6: Ventilation and Oxygen Uptake
During Submaximal Exercise

(liters/min)
A B
64.7 57.2
60.4 48.4
58.6 52.0
59.9 50.1
60.8 59.0
60.8 47.2
53.4 40.9
42.3 42.0
47.6 44.9
47.9 40.9
55.6 48.2

( 7.4) ( 6.4)

Level 1 Ventilation

Oxygen Consumption per Minute
02 per Minute per Body Weight
02 per Minute per Test Weight
Level 2: Ventilation

Subject

OIOQ\)O\UI-waI—'

g..-

Mean
(s.d.)

(liters/min)
A B
86.4 76.0
75.7 61.8
72.3 61.8
82.5 65.4
86.4 69.1
81.0 61.8
74.5 57.7
55.6 54.5
62.0 52.6
61.4 48.9
73.8 61.0

(10.9) ( 3.0)

Level 2 Ventilation

Oxygen Consumption per Minute
02 per Minute per Body Weight
02 per Minute per Test Weight

Significance:

(liters/min)
A B
2.81 2.51
3.08 2.68
2.48 2.17
2.64 2.58
2.66 2.59
2.48 2.26
2.25 1.89
2.13 1.92
2.15 2.09
2.15 1.98
2.48 2.27
.32) ( .30)

N
10
10
10
10

(liters/min)
A B
3.51 3.11
3.63 3.34
2.88 2.51
3.19 3.16
3.29 3.04
2.88 2.69
2.48 2.36
2.47 2.31
2.62 2.35
2.54 2.29
2.95 2.72
.43) ( .41)
N
10
10
10
10
* p<.05:

Oxygen Uptake

Oxygen Uptake

Oxygen Uptake

(ml/kg/min)

A B A-TW
41.2 36.8 38.1
40.9 35.6 37.8
48.4 42.4 44.1
41.6 40.6 37.1
39.8 38.7 36.3
42.8 39.0 38.8
46.9 39.4 42.0
43.7 39.4 40.0
44.9 43.6 41.5
44.8 41.3 41.5
43.5 39.7 39.7

( 2.8) ( 2.4) ( 2.5)
T P Value
5.00 0.00 **
5.43 0.00 **
5.54 0.00 **
-0.06 0.95

Oxygen Uptake

(ml/kg/min)

A B A-TW
51.5 45.6 47.6
48.2 44.4 44.5
56.3 49.0 51.2
50.2 49.8 44.8
49.2 45.4 44.9
49.7 46.5 45.0
51.7 49.2 46.3
50.7 47.4 46.3
54.7 49.1 50.6
52.9 47.7 49.0
51.5 47.4 47.0

( 2.5) ( 1.9) ( 2.5)
T P Value
7.59 0.00 **
6.58 0.00 **
6.59 0.00 **
0.53 0.61
** p<.01

34

Table 6: (continued)

Level 3: Ventilation Oxygen Uptake Oxygen Uptake

(liters/min) (liters/min) (ml/kg/min)
Subject A B A B A B A-TW
1 116.5 97.6 3.93 3.64 57.6 53.4 53.3
2 92.2 80.6 4.15 3.98 55.1 52.9 50.9
3 88.9 83.2 3.11 2.85 60.7 55.7 55.3
4 100.4 86.2 3.67 3.57 57.8 56.2 51.5
5 112.2 88.7 3.75 3.69 56.1 55.2 51.2
6 * 78.1 * 3.09 * 53.4 *
7 * 70.1 * 2.51 * 52.3 *
8 71.5 67.6 2.86 2.66 58.7 54.6 53.7
9 * 64.4 * 2.68 * 55.9 *
10 77.1 56.9 2.83 2.55 59.0 53.1 54.6
Mean 94.1 77.3 3.47 3.12 57.9 54.3 53.0
(s.d.) (16.8) (12.5) ( .53) ( .55) ( 1.9) ( 1.4) ( 1.7)
N T P Value
Level 3 Ventilation 7 5.00 0.00 **
Oxygen Consumption per Minute 7 5.72 0.00 **
02 per Minute per Body Weight 7 4.84 0.00 **
02 per Minute per Test Weight 7 1.81 0.12
Significance: * p<.05; ** p<.01

35
heart rates may be related to thermal effects as the

subjects, when wearing full equipment, may have had more

difficulty dissipating heat following maximal exercise.

Blood Pressure

The blood pressure measurements taken immediately
following each exercise level showed no statistical
significance (Table 4). Those taken five and ten minutes
after the subject stopped running were significant only in
the diastolic blood pressure after five minutes (Table 5).
The blood pressure values appear stable enough that any
potential differences were not significant with this small

sample size.

Ventilation and Oxygen Consumption

The increase in ventilation due to the hockey equipment
was highly significant at each of the three levels of
submaximal exercise (Table 6). (The three subjects who
reached maximum oxygen uptake in Level 3 while wearing their
equipment were not included in the t-test for Level 3.)
Oxygen consumption, in both liters per minute and
milliliters per kilogram of body weight per minute, was
similarly significant. However, when the oxygen consumption
was adjusted for the total test weight - body weight in one
case and body weight plus equipment weight in the other -

there were no significant differences. At Level 3 the

36
difference was nearly one standard deviation, but with only

seven subjects, was not statistically significant.

At each level, the weight of the hockey equipment
caused the subjects to operate at a higher percentage of
their maximum oxygen uptake. Thus peak performance was
reached sooner, decreasing the total run time. The oxygen
consumption relative to total test weight remained steady,
indicating that the energy cost to move the weight was the
same whether the weight was artificial or natural. There was
an increasing effect on the oxygen consumption relative to
total test weight as the subject approaches maximum effort.
This most likely was due to the extra work involved in
moving the shinpads with each stride.

The total volume of oxygen consumed during each of the
three rest periods increased significantly when the subjects
were wearing their equipment, although the increase in
oxygen uptake relative to body weight was significant only
for two, possibly due to the reduced sample size (Table 7).
The subjects were running a substantially increased oxygen
debt when wearing their equipment. In a test without rest
periods, the total running time likely would be shortened
even more drastically.

Neither oxygen uptake nor total oxygen consumed
differed significantly during the post-exercise recovery
period. The recovery period was preceded by a run to

exhaustion in both tests: one just took longer.

37

Table 7: Total Oxygen Uptake During Rest and Recovery

Rest 1 V02 Rest 2 V02 Rest 3 V02
(liters) (liters) (liters)
Subject A B A B A B
1 2.11 1.69 2.60 2.01 3.15 2.65
2 2.15 1.93 2.55 2.32 3.14 2.69
3 1.72 1.56 2.06 1.89 4.24 2.25
4 1.86 1.82 2.36 2.09 2.82 2.43
5 2.08 2.02 2.50 2.44 2.94 2.80
6 1.83 1.73 2.17 1.94 * 2.23
7 1.58 1.32 1.89 1.60 * 1.95
8 1.50 1.23 1.67 1.41 2.14 1.65
9 1.65 1.50 1.97 1.58 * 1.99
10 1.53 1.12 1.83 1.64 1.92 1.87
Mean 1.80 1.59 2.16 1.89 2.91 2.25
N T P Value
Rest Period 1 Oxygen Used 10 4.96 0.00 **
Rest Period 2 Oxygen Used 10 5.98 0.00 **
Rest Period 3 Oxygen Used 7 2.33 0.03 *
Rec. + 5 v02 Rec. +10 v02
(liters) (liters)
Subject A B A B
1 5.60 4.86 8.35 7.65
2 6.52 5.76 9.53 8.65
3 4.52 4.27 6.64 6.21
4 4.33 5.28 6.87 7.87
5 6.39 6.53 9.72 9.66
6 4.35 4.84 6.76 7.22
7 3.77 3.83 6.16 5.86
8 3.92 4.08 5.91 6.10
9 3.81 3.82 5.93 6.48
10 3.91 4.06 5.87 6.15
Mean 4.71 4.73 7.17 7.19
(s.d.) (1.06) (0.90) (1.49) (1.27)
N T P Value
5 Min. Recovery Oxygen Used 10 -0.13 0.55
10 Min. Recovery Oxygen Used 10 -0.06 0.52
Significance: * p<.05; ** p<.01

38

Table 7: (continued)
Rest 1 RVO Rest 2 RVO Rest 3 RVO
(ml/kg/min (ml/kg/min (ml/kg/min
Subject A B A B A B
1 13.3 9.3 15.5 12.5 20.2 16.9
2 11.5 13.0 12.8 14.1 18.3 15.4
3 15.1 12.5 16.4 15.4 20.1 18.3
4 13.1 13.6 14.7 14.8 14.8 17.6
5 13.8 14.3 14.9 16.7 21.7 18.9
6 13.1 12.8 17.8 14.6 * 17.3
7 14.1 11.9 17.5 14.4 * 18.2
8 13.2 11.6 15.3 12.0 18.3 13.5
9 16.0 14.4 18.3 15.1 * 18.8
10 15.3 11.0 16.6 15.6 17.5 18.1
Mean 13.9 12.4 16.0 14.5 18.7 17.3
(s.d.) ( 1.3) ( 1.6) ( 1.7) ( 1.4) ( 2.2) ( 1.7)
N T P Value
Rest Period 1 Oxygen Uptake 10 2.29 0.02 *
Rest Period 2 Oxygen Uptake 10 2.32 0.02 *
Rest Period 3 Oxygen Uptake 7 1.78 0.06
Rec. + 5 Rvo2 Rec. +10 RV02
(ml/kg/min) (ml/kg/min)
Subject A B A B
1 9.1 9.7 7.8 7.7
2 10.0 9.2 7.1 7.4
3 8.7 9.4 8.2 7.3
4 9.0 8.8 7.3 7.7
5 13.8 10.9 9.5 8.9
6 8.1 9.2 7.7 7.5
7 8.9 9.3 11.0 8.2
8 9.8 9.6 7.3 8.2
9 9.7 10.0 8.5 12.3
10 8.5 11.0 7.7 8.2
Mean 9.6 9.7 8.2 8.3
(s.d.) (1.6) (0.7) (1.2) (1.5)
N T P Value
Recovery + 5 Min. 02 Uptake 10 -0.34 0.63
Recovery + 10 Min. 02 Uptake 10 -0.25 0.60
Significance: * p<.05: ** p<.01

39

Blood Lactate Concentration

The increase in blood lactate concentration following
each exercise period was statistically significant after the
second and third levels, but not after the first (Table 8).
The excess weight, particularly on the legs, may have caused
fatigue problems at higher levels of exercise. The decrease
in peak lactate concentration, most likely caused by the
sharply decreased total run time, was not significant.

The lactate levels remained lower all through recovery,
although they showed no significant differences up to 60
minutes following maximal exercise. The percentage of the
increase in blood lactate concentration that was removed
during recovery showed no differences up to 60 minutes
following exercise (Table 9). The hockey equipment did not

change the rate of elimination of the lactate.

Anaerobic Characteristics

The anaerobic tests showed significant differences due
to the hockey equipment in peak power generated and mean
power generated over thirty seconds (Table 10). There was no
change in the percentage of the peak power being produced at
the end of thirty seconds or in the post-test blood lactate
concentration. The differences likely were due, once again,
to the weight of the shinpads. Since the subject was seated,
the remainder of the equipment Should have had little

effect.

Subject

OWQQO‘U‘I-waH

p.»

Mean

(s.d.)

40

Table 8: Blood Lactate Concentration

Pre-Test

(mmol/l)

A B
1.65 1.65
1.80 3.00
2.70 2.30
2.05 1.70
1.60 2.05
1.55 1.80
1.40 1.85
1.45 2.10
1.10 1.95
1.95 2.30
1.73 2.07
( .44) .40)

Pre-Test Lactate Conc.
Level 1 Lactate Conc.

Level 2 Lactate Conc.
Level 3
(mmol/l)
Subject A B
1 8.90 7.10
2 8.75 6.55
3 10.45 7.60
4 11.25 6.80
5 10.00 6.40
6 * 7.20
7 * 9.50
8 8.55 6.95
9 * 8.40
10 9.50 6.75
Mean 9.63 7.33
(s.d.) ( .99) .96)
Level 3 Lactate Conc.

Peak Lactate Concentration
Recovery + 5 Min. Conc.

Significance:

Level 1 Level 2
(mmol/l) (mmol/l)

A B A B
3.40 3.25 5.20 3.75
4.45 4.15 4.55 4.75
3.80 3.15 5.90 4.25
4.10 3.30 5.85 4.65
3.75 3.95 5.60 4.50
4.65 3.20 7.55 4.10
6.35 4.25 10.15 6.00
2.55 3.50 4.25 4.25
3.50 4.65 5.90 5.35
4.45 4.40 6.55 5.25
4.10 3.78 6.15 4.69

(1.00) ( .56) (1.69) ( .68)
N T P Value

10 -2.17 0.06

10 1.02 0.17

10 3.35 0.00 **

Peak Conc. Rec.+ 5 Min.

(mmol/l) (mmol/l)

A B A B
10.20 11.95 8.70 10.05
12.95 14.50 12.15 12.45
12.15 9.65 10.25 8.90
13.75 12.75 12.80 11.75
18.30 15.15 18.30 15.15
10.60 10.80 9.90 10.10
10.80 11.85 9.70 10.05

9.20 12.65 7.35 11.30
11.10 18.55 9.95 16.35
9.85 13.25 7.70 11.20
11.89 13.11 10.68 11.73
(2.66) (2.50) (3.18) (2.37)

N T P Value
7 7.19 0.00 **

10 -1.23 0.12

10 -1.17 0.13
* p<.05; ** p<.01

Table 8:
Rec.+ 10 Min.
(mmol/l)
Subject A B
1 7.10 8.75
2 10.70 10.30
3 8.70 7.35
4 10.55 10.10
5 16.20 13.65
6 8.00 8.90
7 7.85 8.70
8 5.75 9.50
9 8.95 14.85
10 5.90 9.95
Mean 8.97 10.21
(s.d.) (3.04) (2.32)

Recovery + 10 Min. Conc.
Recovery + 15 Min. Conc.
Recovery + 60 Min. Conc.

Significance:

41

(continued)
Rec.+ 15 Min. Rec.+ 60 Min
(mmol/l) (mmol/l)
A B A B
6.00 7.25 2.80 1.80
8.45 8.45 2.55 3.15
7.25 5.55 3.60 2.00
9.55 7.65 2.75 2.95
14.85 10.50 3.75 2.85
6.55 7.55 3.70 2.90
6.45 7.35 2.20 2.20
4.50 7.95 2.45 2.80
6.75 13.10 1.55 4.45
4.70 8.15 1.85 2.85
7.51 8.35 2.72 2.80
(3.00) (2.07) .77) .74)
N P Value
10 -1.48 0.08
10 -0.87 0.20
10 -0.18 0.43
* p<.05; ** p<.01

42

Rec.+ 5 Min.

Table 9: Blood Lactate Concentration Recovery Percentage

Rec.+ 10 Min.

(percent) (percent)
Subject A B A B
1 17.5 18.5 36.3 31.1
2 7.2 17.8 20.2 36.5
3 20.1 10.2 36.5 31.3
4 8.1 9.0 27.4 24.0
5 0.0 0.0 12.6 11.4
6 7.7 7.8 28.7 21.1
7 11.7 18.0 31.4 31.5
8 23.9 12.8 44.5 29.9
9 11.5 13.3 21.5 22.3
10 27.2 18.7 50.0 30.1
Mean 13.5 12.6 30.9 26.9
(s.d.) ( 8.5 6.1) (11.4) ( 7.2)
N T P Value
Percent Recovery at 5 Min. 10 0.40 0.65
Percent Recovery at 10 Min. 10 1.30 0.89
Rec.+ 15 Min. Rec.+ 60 Min.
(percent) (percent)
Subject A B A B
1 49.1 45.6 86.6 98.5
2 40.4 52.6 93.3 98.7
3 51.9 55.8 90.5 104.1
4 35.9 46.2 94.0 88.7
5 20.7 35.5 87.1 93.9
6 44.8 36.1 76.2 87.8
7 46.3 45.0 91.5 96.5
8 60.6 44.5 87.1 93.4
9 43.5 32.8 95.5 84.9
10 65.2 46.6 101.3 95.0
Mean 45.8 44.1 90.3 94.2
(s.d.) (12.5) ( 7.4) ( 6.7) ( 5.8)
N T P Value
Percent Recovery at 15 Min. 10 0.47 0.67
Percent Recovery at 60 Min. 10 -1.45 0.09
Significance: * p<.05: ** p<.01

Table 10: Anaerobic Characteristics

43

Peak Power

Mean Power

(watts/kg) (watts/kg)
Subject A B A B
1 7.24 7.24 6.12 6.42
2 7.93 7.65 6.56 6.33
3 7.75 8.61 5.69 6.22
4 8.06 8.33 6.76 6.71
5 7.91 8.44 6.97 7.16
6 7.11 6.85 5.75 5.75
7 6.61 6.86 5.23 5.56
8 7.00 7.49 5.55 5.96
9 6.38 6.87 5.60 5.48
10 7.11 7.11 6.12 6.25
Mean 7.31 7.55 6.04 6.18
(s.d.) ( .58) ( .69) ( .57) ( .52)
N T P Value
Peak Power 10 -2.01 0.04 *
Mean Power 10 -1.91 0.04 *
% Power at 30 Sec Post-Test Lactate
(mMol/l)
Subject A B A B
1 71 82 9.15 9.80
2 66 68 12.20 10.50
3 56 50 10.15 8.90
4 72 71 12.35 12.10
5 80 77 13.55 14.35
6 64 67 11.00 10.40
7 72 73 11.20 9.80
8 62 67 11.30 11.90
9 80 76 8.60 9.80
10 81 89 11.05 10.95
Mean 70 72 11.06 10.85
(s.d.) ( 8) (10) ( 1.48) ( 1.58)
N T P Value
% Power at 30 Seconds 10 -2.08 0.19
Post-Test Lactate 10 -1.23 0.27
Significance: * p<.05; ** p<.01

44
Summary

The acceptance and rejection of the research hypotheses
are summarized in Table 11. No decision could be made on
three of the hypotheses regarding the changes in heart rate.
While there were instances of statistical significance
during exercise, the differences are below the one-half of a
standard deviation earlier required to be significant and
also are at or below the limit of resolution of the heart
rate monitor at high heart rates. The differences noted
during recovery may be strongly influenced by thermal

effects outside the scope of this study.

a)

h)

f)

9)
h)

i)

3')

k)

45

Table 11: Summary of Research Hypotheses and Judgements

Hypothesis

Performing the tests while wearing
hockey protective equipment will:

decrease the total run time

increase the heart rate during
exercise,
rest,
and recovery

increase the blood pressure during
exercise,
and recovery

decrease the peak heart rate

increase the ventilation
and oxygen uptake per body weight
but show no change relative to
test weight

decrease the maximum oxygen uptake
increase the oxygen consumption

during rest

and recovery
increase the blood lactate concentration

decrease the peak lactate concentration

decrease the percent recovery of blood
lactate concentration

Show no decrease in anaerobic
peak power,
mean power,
and percent power at 30 seconds,

show no increase in post-test blood
lactate concentration

Judgement

Accepted

No Decision

Accepted

No Decision

Rejected
Rejected

No Decision

Accepted
Accepted

Accepted
Rejected
Accepted
Rejected
Accepted

Rejected

Rejected

Rejected
Rejected
Accepted

Accepted

46

Chapter V - Conclusions and Recommendations

The results of this study indicate that wearing hockey
protective equipment had substantial detrimental effects on
the subjects’ maximum performance on the treadmill test as
determined by the external factor of total running time.
When the criteria involve internal factors, for example,
maximum oxygen consumption and peak blood lactate
concentration, there was no difference in the maximum effort
involved. At submaximal levels of exercise, the weight of
the hockey equipment caused each subject to operate at a
higher percentage of his maximum capacity, thus decreasing
the duration of the performance.

The part of the excess weight attached to the legs -
the player's shinpads - has an effect out of proportion to
the remaining weight. While not strictly isolated in this
study, this effect is most noticeable in the anaerobic
bicycle tests, and likely accounts for most of the rapid
divergence in the blood lactate concentrations between the
experimental and control condition. Further studies should
plan to test subjects with and without shinpads, or with
shinpads and an equivalent weight attached to the upper
body.

While the thermal effects of the hockey equipment were

not within the scope of this study, they are deserving of

47
study. The equipment and garments worn by the players were

intended to insulate them from the cold environment in which
they normally practice and compete. Particularly during
recovery, the players indicated they were warm, and most
removed part of their equipment while waiting the forty five

minutes until the bicycle test.

Recommendations Relating to the Study

The pre-test heart rate and blood pressure measures
showed no differences. The pre-test blood lactate
concentration, however, showed a difference of well over
half of a standard deviation. While not statistically
Significant with only ten subjects, there may be an effect
there. Possibly the subjects were more active while waiting
for their tests to begin on the day they did not wear their
equipment. A future study may need to include restrictions
on the subjects' pre-test activities.

The heart rate monitor had difficulty discriminating
heart beats when the rate was over 200 beats per minute,
with the result that the displayed number would fluctuate,
sometimes wildly, around the presumably true value.
Unfortunately, it is at this point of maximum or near
maximum effort that the most accurate data is needed. Future
studies in this area should address the problem of
resolution at maximum heart rates.

Although the Wingate anaerobic capacity test had

statistically significant findings, it may not be the most

48
appropriate test for this type of study. In particular, the

non-weight bearing character of a bicycle test limits
application of these findings to an on-ice Situation.
Further studies should consider replacing it with a second
treadmill test of shorter duration, higher speed, and higher
grade. This would more accurately reflect the bursts of high

intensity effort frequently required of hockey players.

Recommendations Relating to the Hockey Protective Equipment

The obvious recommendation is to make the protective
equipment as lightweight as possible while still allowing
the equipment to perform its function. However, each
marginal improvement in the weight of the equipment comes at
an increasing marginal cost in development and production,
and therefore in purchase price. There soon comes a time
when the next step is so expensive that no one could afford
to make the equipment, or to purchase it if it was made.
Sufficient information on the energy cost of the equipment
would help manufacturers balance the economic cost against
the added benefit of the lighter product. More specifically,
there may be a relationship between maximum oxygen
consumption relative to body weight and equipment weight
such that an optimum equipment weight could be determined to
allow a player to perform at, for example, 80 percent of his
unweighted maximum.

The distribution of the weight also plays a role in the

effects on performance. Weight attached to the legs -

49
shinpads and, though not covered in this study, ice skates -

acts disproportionately to decrease a player's performance.
A manufacturer should spend correspondingly more weight
reduction efforts on these pieces of equipment than on
others. Further study may establish a second relationship
between performance and weight on the legs that would
determine an optimum weight of shinpads and skates to

achieve a given level of performance.

Recommendations Relating to the Hockey Players

Players could also use this information to make
decisions on the protection versus performance trade-off of
new equipment. For example, subject number seven was the
smallest player yet wore one of the heaviest pairs of
shinpads. He most likely could have found adequate
protection in lighter equipment and increased his
performance and endurance on the ice. Similarly, subject
number five was one of the larger players yet wore one of
the lighter pair of pads. He perhaps could have gotten some
additional protection without seriously impairing his
performance.

Hockey players also should consider training wearing a
weight vest and/or ankle weights to simulate their
equipment. Most wear their equipment for on-ice training.
Some wear extra weight for their off-ice training. However,
the training, and hence the adaptations, could be made

specific to the weight the player would be carrying.

50

Summary

The effects of protective equipment deserves continuing
study to monitor the costs - in energy and economics - and
benefits - in performance and protection - that it provides
to the athletes it is protecting. In the sophisticated world
of professional and international competition, seemingly
minor changes may mean the difference between success and
failure. The evolution of the sport, modern technology, and

new ideas ensure that those changes come quickly.

LIST OF REFERENCES

51

LIST OF REFERENCES

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