The Effects of Varying Saddle Heights on Energy Expenditure in Cycling

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Nov 14, 2013 (3 years and 11 months ago)

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The Effects of Varying Saddle Heights on Energy Expenditure in Cycling

Daniel Sowada

Minnesota School of Business















1


TABLE OF CONTENTS

INTRODUCTION
……………………………………………………………………………….
..
2

LITERATURE REVIEW
………………………………………………………………………..
.
4

METHODS
………………………………………………………………………………………
.
9

RESULTS………………………………………………………………………………………..
10

DISCUSSION…………………………………………………………………………………..
.
.
1
1

REFERENCES…………………………………………………………………………………
..
1
3

APPENDIX A…………………………………………………………………………………..
.
1
5

APPENDIX B……………………………………………
……………………………………...1
6

APPENDIX C…………………………………………………………………………………...1
7

APPENDIX D…………………………………………………………………………………...1
8















2


INTRODUCTION

Cycling

is great
cardiovascular
exercise, but more harm than good can come from that
ride as well.
M
any individuals
ride

bikes that are not set
-
up properly,
such as
saddle height too
low/high,
and the
h
andlebars not adjusted properly.


Saddle height should be comfortable for the
rider. One should not have to plantar flex in excess to reach the pedal on
the down
-
swing, and in
contrast one’s knees should not be hitting the bars either.
T
he mechanics of the cycling motion
will be
inconsistent

if pre
-
ride adjustments are not made.
Not only will performance be affected
but one’s knees could be
comp
romised

i
n the process.

The mechanics of the
pedaling

motion
in cycling
are repetitive. With this
repetition
may
come

an over
-
use injury

typically

seen

at the knee.
T
o prevent these over
-
use injuries, a saddle
height must be used where the knee is under
the least

amount of stress. When stress is taken off
the knee
,

force

can be
better
focused

to

other areas such as the pedaling motion
,

making
it

more
efficient

allowing

one
to

ride more
.

Enough knee flexion is needed to avoid a dead spot at the
bottom dead cente
r of the pedal stroke.
At this position
patellar compression is reduced (15).

What is the optimal saddle height for cycling? There are
different

theories

for the answer
to this question
. The National Strength and Conditioning Association (NSCA) protocol

on
saddle height
of

a stationary bicycle
when performing a
cardio respiratory

endurance assessment

is
knee
flex
ion

between 25
-
35 degrees
,

with the pedal in the down position (
3
,8,15
). This
recommendation

is used so as to avoid any injuries
associated wit
h

excessive anterior knee pain
with too low of a saddle height o
r too high of a saddle height (
5
).

For the recreational cyclist injury prevention should be the goal. When the cyclist avoids
injury, they are able to ride more, thus raising their activity level and leading a healthier life
-
style. Those in competition however have a different focus. Com
petitive riders are more
focused on performance
related to energy expenditure
and less on injury prevention. With this
being said saddle hei
ghts tend to be slightly higher.

3




The Hamley method for finding saddle height uses 109% of inseam, which is sugges
ted
for optimal performance but falls out of the
25
-
35 degree
knee angle

recommended by Holmes
for injury prevention
. However, according to the American Council of Sports Medicine (ACSM)
the protocol for cycle ergometry is establishing a saddle height whe
re the knee is flexed between
5
-
10 degrees while sitting on the seat with the pedal in the down position (
1
).
Increased force
production
by the glute
us maximus, hamstrings, and quadriceps

is the result of a decrease in

knee angle because there is a longer

downswing.


Saddle height is about personal preference and if one feels comfortable at that position.
For the recreational cyclist being comfortable while riding is an important factor. Eye
-
balling
the pedaling motion to obtain a saddle height is ano
ther method that is a little less scientific but is
used to obtain the same results and effectiveness

(4)
. When eye
-
balling the pedaling stroke
from
behind the rider,
there should be no
rocking of the pelvis

which results from too high of
a
saddle
height.

The pedaling motion should be smooth and
consistent

with no
rocking of the pelvis

(8)
.


Heart rate plays
a

key factor in determining correct saddle height
for the cyclist
. When
the mechanics are wrong in the cycling motion, the body will tend to compe
nsate
, resulting in
increased energy expenditure, indicated by higher heart rates
.



The
purpose

of this study is to find what saddle height is more
energy
efficient in
recreational cyclists.









4


LITERATURE REVIEW

Peveler et al compared multiple
methods of finding the optimal saddle height for cycling.
It was recommended by Holmes to use a knee angle between 25
-
35 degrees to prevent overuse
injuries. The Hamley method uses 109% of inseam measured from the pedal axle to the top of
the seat. The
Greg Lemond method uses 88.3% of inseam and measures from center of the
bottom bracket to the top of the saddle; the heal
-
toe method (Holmes method) places the heal on
the distal pedal position while cyclist is on the saddle

(9)
.


Nineteen cyclists parti
cipated in the study. They all used their own bikes for the tests
which were placed on stationary trainers. Leg inseam length was measured in centimeters with a
metric ruler. Once on the bike, knee angles were measured using a goniometer at the varying
saddle heights. The means of the different methods were compared to see how often the knee
angle fell within Holmes recommended angles of 25
-
35 degrees
.


There was no significant difference between the Hamley method and Lamond method.
There was a signifi
cant difference between the Hamley method and heel
-
toe method (Holmes
method). The mean knee angle of the Hamley method was 24.2 degrees, for the Lemond method
it was 24.3 degrees, and lastly for the
Holmes

method the mean knee angle was 30.3 degrees.
Th
e
Holmes

method fell in the middle of the recommended knee angle for injury prevention and
was shown to be the most accurate method for finding optimal sadd
le height for injury
prevention.

Peveler conducted a study on the effects of saddle heights on economy in cycling. He
used the knee angles, measured with a goniometer, of 25 degrees and 35 degrees to determine
proper saddle height. These knee angles were recommended by Holmes et al. for

injury
prevention while cycling. Too high as well as too low of saddle heights can cause knee pain,
leading to compensatory factors and injury. Hamley and Thomas determined that 109% of
5


inseam was the most efficient in terms of performance. Peveler use
d this for the third saddle
height

(11)
.

There were 15 participants in Peveler’s study. All subjects were asked to wear the same
shoes during each trial in order to prevent any changes in sole thickness which could have an
effect on testing. Subjects w
ere asked to report to the laboratory four separate times. The first
visit was to test for Vo2 max using a Monark ergometer; this would determine the subject’s
individualized testing workload. Pedaling cadence for noncyclists was kept at 50 rpm and
cycli
sts at 90 rpm
.

A graded exercise protocol was used. The resistance was set at 1kp and increased .5kp
every 2 minutes. The test continued until subjects could not keep up with the pedaling cadence;
this would give them their Vo2 max. For the remaining th
ree visits subjects were put on the bike
at a set saddle height where they were to pedal for 15 minutes with their individualized
intensities.

Vo2, HR, and RPE were compared among the total group as well as the subgroups,
cyclists (n=7) noncyclists (n=10
) men (n=7) and women (n=8). A significant difference was
found in the total group between the knee angles of 25 degrees and 35 degrees as well as a 25
degree knee angle and 109% of inseam. Vo2 was lower at a knee angle of 25 degrees than 35
degrees as w
ell as 109% of inseam. There was no difference in VO2 with a 35 degree knee
angle and 109% of inseam. These results indicate that cycling efficiency is optimal when the
knee angle is approximately 25 degrees.


Shennum and deVries had their subjects pedal

at increasing workloads ranging from 50
watts to 200 watts in 25 watt increments at varying saddle heights to determine oxygen
consumption at each saddle height. Saddle heights were randomized between the subjects so as
to avoid any order. Five saddle h
eights were used: 100%, 103%, 106%, 109%, and 112% of
6


inside leg length when measured from the ischium to the floor. Saddle height was then measured
from the top of the saddle to the distal position of the pedal

(12)
.

Five experienced cyclists were used f
or the study in order to avoid any novice errors.
All subjects owned a racing style bicycle that the testing ergometer was adapted to simulate.
Each rider started out at 50 watts at a pedaling cadence of 60 rpm. Every three minutes Vo2,
VCo2, VE, and
HR were recorded and the resistance was increased 25 until 200 watts was
reached. Tests were conducted every other day using a different saddle position.

At the highest position, 112%, energy expenditure was at its highest and was thus the
least efficie
nt. It was found that Vo2 was at its lowest at the lower ischium to floor
measurements of 100% and 103%. Significant differences in Vo2 were found between the
100%
-
109% where Vo2 was at its lowest in the lower saddle positions.


Nordeen
-
Snyder measure
d trochanteric lengths via tape measurement and applied them
to three different saddle heights of 95, 100, and 105% to see if the varying kinematics had an
effect on oxygen consumption

(7)
.

10 female participants between the ages of 18 and 31 were used i
n the study. The bike
that was used for the test was set on rollers so practice sessions were used to familiarize them
with riding on rollers.

Workloads stayed at 60 rpm until a steady state HR was reached, successive heart rate
readings within 5 beats
per minute (
2
), which took around 8
-
9 minutes. As soon as a steady state
was reached expired air was collected for the next 3 minutes. This procedure was repeated two
more times, after 10 minute breaks in between each test, at the remaining seat heights.

The results for oxygen consumption at the low, medium, and high saddle heights were
1.69, 1.61, and 1.74 liter/minute respectively. From these findings there was a significant
difference on oxygen consumption at the 100% and 105% saddle height where 100%

appeared to
be the most efficient in terms of oxygen consumption.

7



Tamborindeguy and Bini examined patellofemoral and tibiofemoral forces at varying
saddle heights. An inverse relationship between saddle height and shear fo
rces was expected
(13).


Ther
e were nine participants in the study. Each participant was measured from their
greater trochanter to the floor to obtain trochanteric length. This measurement was used to attain
a saddle height.


A Monark ergometer was used for the tests. The saddle
heights were set at 100%, 103%,
and 97% of trochanteric height. Workloads were set at 70 rpm and 70 watts and participants
were told to pedal for 1 minute at each saddle height. Participants were asked to stand for the
saddle height changes and continue
pedaling while knee joint forces were recorded from the
instrumental two
-
dimensional right clipless pedal which was designed for force measurement.


There were no significant changes in patellofemoral and tibiofemoral forces at varying
saddle heights.

The conclusion was made in the present study that the differences in saddle
heights were too low to make a difference in shear force.




Houts et al conducted an analysis of muscle action and joint excursion during exercise
on a stationary bicycle. The

purpose of the study was correlate electromyographic observations
of surface muscles thought to participate in exercise on a stationary bicycle with accompanying
joint range studies

(6)
.

There were three subjects in the study. Two saddle heights were u
sed, one at twenty
-
one
inches measuring from the center of the pedal to the top of the saddle, and the other was raised
four inches to 25 inches.

The bicycle being used was that which would be found in most physical therapy centers
(at the time, 1959).
Resistance was calculated using a small fish scale which was incorporated
into the braking mechanism. Resistance increased steadily starting with no resistance then to
8


1.5, 3, 4, 4.5, and 5 pounds. Subjects were instructed to pedal at an easy pace and to

perform as
smoothly as possible, while keeping the feet in the same position on the pedals.

It was found that the magnitude of action potentials and the number of muscles
contracting increased with added resistance. With the higher resistances the patt
ern of action of
each muscle remained discrete in its timing, meaning the muscles that contribute to the pedaling
motion fire in the same pattern regardless of resistance.

Changing the height of the saddle did not influence the pattern of muscle action.

The
majority of the muscle actions were less when pedaling at the higher saddle height compared to
the low saddle height against the same resistance. The ease at which the subjects pedaled against
heavy resistance in the high saddle position was obvious
to both the subject and operator. The
results may indicate that varying the saddle height of the bicycle seat does not influence, in
general, the timing of the muscle activity, but the exercise is performed with less effort when the
seat is high. This st
atement suggests that at a higher saddle height less energy is being used
while cycling.












9


METHODS


Subjects for this study were students/faculty volunteers from the Minnesota School of
Business campus. Subjects were free from any heart rate altering medications and were also
informed not to partake in any caffeinated beverages or nicotine 2 hours prior

to testing, as they
may cause a temporary rise in heart rate and blood pressure. Saddle heights were determined
using the Hamley method, 109% of inseam measuring from the pedal axel to the top of the
saddle, the Greg LeMond method, 88.3% of inseam measur
ing from the bottom bracket to the
top of the saddle, and the Holmes method, measuring the knee for an angle between 25
-
35 with
the pedal in the down position. Inseam measurements were taken using a tape measure, with the
shoes on, which were then used fo
r the Lemond and Hamley methods. A goniometer was used
to obtain knee angle measurements from the leg in the most distal pedal position.


A Monark Ergometic 874 E was used for testing

(Appendix B)
. Pedaling workload was
set at 30 watts with a cadence o
f 60 rpm, with .5 kp resistance. Participants rode at a constant
workload until a steady state heart rate was obtained. Heart rates were measured, via a Polar
heart rate monitor, after the first two minutes and every minute until 2 successive heart rate
readings
were within 5 beats per minute

(
2
). Once all information was recorded the participant
was given a 10 minute break before the next test. Saddle height was changed and the process
was repeated for the remaining two heights. Saddle heights were ra
ndomized to avoid
an order
effect
.

Subjects were asked to refrain from any speaking during the testing as this could have an
effect on heart rate readings. Inspection of pedaling motion was observed so as to prevent any
rocking of the hips. A consent f
orm was read and signed by the participants explaining the test
and the risks of exercise

(Appendix C)
. The data was analyzed using a
one
-
way

analysis of
variance (ANOVA) with a significance level of p ≥ .05

(Appendix D)
.


10


RESULTS


Anova: Single Factor














TABLE 1







Groups

Count

Sum

Average

Variance



Hamley

7

857

122.429

921.619



Holmes

7

834

119.143

1165.14



Lamond

7

860

122.857

831.476

















TABLE 2







Source of Variation

SS

df

MS

F

P
-
value

F crit

Between Groups

57.8095

2

28.9048

0.02971

0.97077

3.554557

Within Groups

17509.4

18

972.746











Total

17567.2

20











The mean heart rate values for each saddle height are summarized in Table 1. Heart rate
data was subjected to an analysis of variance to determine if significant differences existed with
respect to saddle height (Table 2). For the data to be significant
an

F value of >1.0 was required.












11


DISCUSSION


The null hypothesis has been confirmed that varying saddle heights do not
have
significant
effect on energy expenditure.
The two saddle heights geared more towards
performance
, Hamley and Lamond,

were virtually identical when it came to average heart rates.
We compare th
ose

to the Holmes method which is used for injury prevention and heart rates
were
approximately

3 beats lower
,

but

not enough to be significant.

It is possible that at a higher
saddle height, one’s torso is put into a position where there
is increased flexion, thereby putting increased pressure on the diaphragm causing the pulmonary
system to expend more energy.
For this very reason it is wise to calculate upper body position
,
d
ictated by handlebar adjustment,

as well as knee angles when trying to find optimal cycling
position for the lowest possible energy expenditure.
It is recommended to have the handlebars
one to five centimeters lower than the seat, however some younger rid
ers can have a drop as
much as twelve centimeters. Flexibility and core strength must be taken into consideration as
well when setting a handlebar height (8).

With a knee angle between 25
-
35 degrees with the foot in the distal pedal position it may
help t
o conserve energy over the higher saddle heights because the muscles of the thigh do not
have
work as hard
. Muscles generate heat, and a muscle that does more work will generate more
heat thus more blood will travel to the working muscles and raise blood
pressure causing an
increase in heart rate.

We have to take into consideration the limited number of subjects used for the study.
There were 7 subjects that participated in the study limiting
any

statistical power. For the
convenience of time, all 3 te
sts for the varying saddle heights were performed within 10 minutes
of each other. Naturally with exercise over a period of time one tends to tire, and the muscles
become weakened from exertion. What was taking place on a majority of the tests was that h
eart
rates were increasing with each test and as time went on.

Saddle height could only be adjusted
12


by 1 inch increments, as this is what the bike would allow. By being allowed to move the saddle
higher or lower 1 inch at a time eliminates the chance of

getting the desired height.
Subject
fitness level ranged from beginner to athlete cycling status. This was considered to be a low
workload cycling study, and a couple of the participants were near age predicted max h
eart rates
after the first test indic
ating it was a high workload for them.


When determining saddle height the rider should know what they want. Is performance
one’s goal where a higher saddle height would benefit
because of the increased downswing of
the pedaling motion? Or is one look
ing for more a recreational use where a
lower
saddle height
geared towards injury prevention
may

be more suitable? Just like any workout program
,

saddle
height should be individualized according to one’s goals.
















13


REFERENCES


1.

ACSM’s Health
-
Related Physical Fitness Assessment Manual
(2
nd

ed.). (2008). Printed in the
USA.

2.

Bryant, Cedric X. 101 Frequently Asked Questions about “Health & Fitness” and “Nutrition &
Weight Control”. Sagamore Publishing, 1999.

3.

Earle, R., Baechle, T
. (2004).
NSCA’s Essentials of Personal Training.
Creative Printing USA.

4.

Empfield, D. (2007, September). Seat height.
Triathlon Is.

5.

Ericson, M., Nisell, R., Nemeth, G. (1988). Joint Motions of the Lower Limb during Ergometer
Cycling.
The Journal of Orthopaedic and Sports Physical Therapy,
9(8), 273
-
278.

6.

Houtz, S., Fischer, F. (1959). An Analysis of Muscle Action and Joint Excursion During
Exercise on a Stationary Bicycle.
The Journal of Bone & Joint Surgery,
41, 123
-
131.

7.

Nordeen
-
Sny
der, K. (1977). The effect of bicycle seat height variation upon oxygen
consumption and lower limb kinematics.
Medicine and Science in Sports,
9(2), 113
-
117.

8.

Olsen, B. Bicycle Fitting Protocol.
Wheel Works.
Retrieved November 22, 2010 from
http://www
.wheelwerksbikes.com/aboutfitting.html
.

9.

Peveler, W., Bishop, P., Smith, J., Richardson, M., Whitehorn, E. (2005). Comparing Methods
For Setting Saddle Height In Trained Cyclists.
Journal of Exercise Physiologyonline,
8(1), 51
-
55.

10.

Peveler, W., Pounders,

J., Bishop, P. (2007). Effects Of Saddle Height On Anaerobic Power
Production In Cycling.
Journal of Strength and Conditioning Research,
21(4), 1023
-
1027.

11.

Peveler, W. (2008). Effects Of Saddle Height On Economy In Cycling.
Journal of Strength
and Co
nditioning Research,
22(4), 1355
-
1359.

12.

Shennum, P., deVries, H. (1976). The effect of saddle height on oxygen consumption during
bicycle ergometer work.
Medicine and Science in Sports,
8(2), 119
-
121.

14


13.

Tamborindeguy, A., Bini, R. (2009). Does saddle hei
ght affect patellofemoral and tibiofemoral
forces during bicycling for rehabilitation?.
Journal of Bodywork & Movement Therapies,
1
-
6
.

14.

Too, D., Landwer, G. (no date). The Biomechanics of Force and Power Production in Human
Powered Vehicles.
Human Po
wer,
55, 3
-
6.

15.

USA Cycling Level III Coach Manual
(Version 2006.1). Printed in the USA.









































15


Appendix A


This research study is being conducted to determine if varying saddle heights have an
effect on energy expenditure. Too often saddle heights are not adjusted to the proper position in
cycling, thus negating optimal performance, because one has to pedal ha
rder leading to an
increase in heart rate. Possible injury at the knee may ensue because of the repetitive nature of
the pedaling motion if proper saddle height is not used as well. While participating in this study
one will gain valuable insight of pro
per saddle positioning.

The testing site will be in the fitness lab of the Minnesota School of Business campus.
Testing will be done on a Monark cycle ergometer at a low workload. Three saddle heights will
be used; each measured using a specific method
. Subjects will pedal at 60 rpm until a steady
-
state heart rate is reached, that is consecutive heart rate reading within 5 beats of each other. Ten
minute rest periods will be given in
-
between saddle height changes. Testing should last
approximately on
e hour.

SUBJECT EXPECTATIONS

1.

Subjects on any heart rate altering medications will not be able to participate

2.

Work
-
out attire only (sweatpants, shorts, t
-
shirts, athletic shoes etc) changing rooms are
available in the lab

3.

Refrain from caffeinated products

at least 2 hours prior to testing*

4.

Refrain from any nicotine products at least 2 hours prior to testing*

*
caffeine and nicotine have been known to increase blood pressure leading to an increase in resting heart ra
te

Contact Information


Danny Sowada

Phone

# 320
-
309
-
6618

Email


daniel.sowada@students.msbcollege.edu


Please leave name, availability, and contact information if interested in participating in the study.

Thank You



16


Appendix
B









Cycling Ergometer that was used for this study







17


Appendix
C



CONSENT FORM

THE EFFECTS OF VARIOUS SADDLE HEIGHTS ON ENERGY EXPENDITURE
IN
CYCLING



You are invited to participate in a research study involving
energy expenditure in cycling
according to various saddle heights. Participants will be tested on a cycle ergometer at a low
workload and heart rate will be measured via a Polar hea
rt rate monitor. The researcher hopes to
learn whether the body expends less/more energy, by fluctuations in heart rate, at one saddle
height over another. You were selected as a possible participant in this study because you meet
the eligibility of part
icipation for this study.



The methods used during this study will be the same for every subject participating. This
study will be conducted using both male and female volunteers. First, subjects will be instructed
to not consume any caffeinated produ
cts or products with nicotine two hours prior to the
ergometer tests. Next, subjects will be instructed to wear loose fitting, exercise appropriate
clothing. This is exercise and with that there will be an increase in heart rate and some instances
where
one may become uncomfortable from heavy respiration and muscle soreness. At any time
during testing subjects may request to stop.



The benefits from this study may include a better understanding of proper saddle
positioning.



All subject’s information will remain confidential in this study in compliance with all
HIPAA requirements. The results of this study will include pre and post test measurements only;
no subject information will be included in the results of this study.



Your decision whether or not to participate will not prejudice your future relations with
the Minnesota School of Business. If you decide to participate in this study, you are free to
withdraw your consent and to discontinue participation at any time w
ith prejudice.



YOU ARE MAKING A DECISION WHETHER OR NOT TO PARTICIPATE. YOUR
SIGNATURE INDICATES THAT YOU HAVE DECIDED TO PARTICPATE, HAVING
READ THE INFORMATION PROVIDED ABOVE.

I acknowledge that I have received a personal copy of this consent form. C
opy received ______


(initial)



__________


________________________


________________________

Date



Print Name





Signature





__________








________________________

Date









Signature of Researcher




18


Appendix
D



SUBJECTS

HAMLEY

HOLMES

LAMOND

1

171
(bpm)

172
(bpm)

166
(bpm)

2

156

161

158

3

114

103

117

4

122

119

122

5

92

91

94

6

109

86

94

7

93

102

109


AVERAGE HEART RATES