The individual pursuit: demands and preparation

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The individual pursuit demands and preparation

• Andrew R. Coggan, Ph.D.

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The individual pursuit a deceptively simple
event favoring specialists who possess superior
aerobic fitness coupled with a high anaerobic
capacity, excellent aerodynamics, and specific
technical skills.
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The pursuit performance teeter-totter
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Physical factors
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The pursuit performance teeter-totter
Rolling resistance/ chain friction Inertia/kinetic
energy Aerodynamic drag
Neuromuscular power Anaerobic capacity Aerobic
power
Faster
Faster
Factors
Factors
Physiological
Physical
Start Line Pacing
Factors
Technical
Faster or Slower
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Mathematical model of the physics of cycling
PTOT (PAT PKE PRR PWB PPE)/Ec PTOT
(0.5?Va2Vg(CdA Fw) 0.5(mt I/r2)(Vgf2 -
Vgi2)/(tf - ti) VgCrrmtgCOS(TAN-1(Gr))
Vg(0.0910.0087Vg) VgmtgSIN(TAN-1(Gr)))/Ec Wher
e   PTOT total power required (W) mt total
mass of bikerider system (kg) PAT power
required to overcome total aerodynamic drag (W)
I moment of inertia of wheels (kgm2) PKE
power required to change kinetic energy (W) r
outside radius of tire (m) PRR power required
to overcome rolling resistance (W) Vgf final
ground velocity (m/s) PWB power required to
overcome drag of wheel bearings (W) Vgi
initial ground velocity (m/s) PPE power
required to change potential energy (W) tf
final time (s) ? air density (kg/m3) ti
initial (s) Va air velocity (relative to
direction of travel) (m/s) Crr coefficient of
rolling resistance (unitless) Vg ground
velocity (m/s) g acceleration due to
gravity (9.81 m/s2) Cd coefficient of drag
(dependent on wind direction) (unitless) Gr
road gradient (unitless) A frontal area of
bikerider system (m2) Ec efficiency of
chain drive system (unitless) FW wheel rotation
factor (expressed as incremental frontal area)
(m2)
(Martin, Milliken, Cobb, McFadden, and Coggan. J
Appl Biomech 14276-291, 1998)
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Validation of modelunder steady-state conditions
(Martin, Milliken, Cobb, McFadden, and Coggan. J
Appl Biomech 14276-291, 1998)
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Validation of modelunder non-steady-state
conditions
Measured speed
Model-predicted speed
Measured power
(Martin, Gardner, Barras, and Martin, unpublished
observations)
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Nominal characteristics of world class pursuiters
used in modeling
Male
Female

• Height 180 cm
• Weight 75 kg
• CdA 0.209 m2
• Pursuit power 540 W
• 4 km time 4 min 25 s

• Height 170 cm
• Weight 65 kg
• CdA 0.197 m2
• Pursuit power 415 W
• 3 km time 3 min 35 s

• Weight of bicycle, etc. 9.0 kg
• CRR 0.002 (i.e., wood track)
• Air density 1.185 g/L

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Absolute and relative power requirementsof
world class pursuit performance
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Time savings resulting from 5 changes in
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Aerodynamics the devil is in the details!
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Field testing using a powermeter to determine
aerodynamic drag characteristics (CdA)
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Technical factors
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The pursuit performance teeter-totter
Rolling resistance/ chain friction Inertia/kinetic
energy Aerodynamic drag
Neuromuscular power Anaerobic capacity Aerobic
power
Faster
Faster
Factors
Factors
Physiological
Physical
Start Line Pacing
Factors
Technical
Faster or Slower
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Time savings resulting from improvements in
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Effect of pacing on 3 km pursuit performance
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Effect of pacing on 3 km pursuit performancewhen
overall average power is equivalent
Time 351.4
Time 353.4
Average 411 W
Average 408 W
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Coggans 1 rule of pursuiting

• Dont go out too hard!
• Dont go out too hard!
• Dont go out too hard!
• Dont go out too hard!

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Physiological factors
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The pursuit performance teeter-totter
Rolling resistance/ chain friction Inertia/kinetic
energy Aerodynamic drag
Neuromuscular power Anaerobic capacity Aerobic
power
Faster
Faster
Factors
Factors
Physiological
Physical
Start Line Pacing
Factors
Technical
Faster or Slower
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The individual pursuit a predominantly aerobic
event
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Energy demands expressed in O2 equivalents
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Power-VO2 relationship (efficiency)
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Time savings resulting from 5 changes in
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Role of VO2max, anaerobic capacity (MAOD) and
aerodynamic drag characteristics (CdA) in
determining 3 km pursuit performance
Rider A
Rider B
Rider A
VO2max 4.47 L/min Efficiency 24.1 Est. MAOD
3.36 L Ave. power 397 W CdA 0.214 m2 3 km
time 347.3
Total
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80
Maximal aerobic
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Role of VO2max, anaerobic capacity (MAOD) and
aerodynamic drag characteristics (CdA) in
determining 3 km pursuit performance
Rider A
Rider B
Rider A
Rider B
VO2max 4.20 L/min Efficiency 23.9 Est. MAOD
5.27 L Ave. power 411 W CdA 0.236 m2 3 km
time 349.7
VO2max 4.47 L/min G.E. 24.1 Est. MAOD 3.36
L Ave. power 397 W CdA 0.214 m2 3 km time
347.3
Total
Total
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20
72
80
Maximal aerobic
Maximal aerobic
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Preparation
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Expected physiological adaptationsas a function
of training intensity
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Proposed relationship between training intensity
and overall aerobic training effect
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Training volume (hours/month)
Pursuit-specific training
LT focus (off-season
build)
VO2max focus (road racing season)
RR
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Typical week during LT focus
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Typical week during VO2max focus
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Typical week during pursuit-specific training
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Use of powermeter data to manage training and
plan peak performance
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A happy ending!