2005 Pan American Sports Organization talk on individual pursuit

The individual pursuit: demands and preparation

Andrew R. Coggan, Ph.D.

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.

The pursuit performance ‘teeter-totter’

Neuromuscular power

Anaerobic capacity

Aerobic power

Factors

Start

Line

PacingTec

hnica

l Factors

Rolling resistance/chain friction

Inertia/kinetic energy

Aerodynamic drag

Phys

ical

Faster F

aste

rFactors

Phys

iolo

gica

l

Faster or Slower

Physical factors

The pursuit performance ‘teeter-totter’

Neuromuscular power

Anaerobic capacity

Aerobic power

Factors

Start

Line

PacingTec

hnica

l Factors

Rolling resistance/chain friction

Inertia/kinetic energy

Aerodynamic drag

Phys

ical

Faster F

aste

rFactors

Phys

iolo

gica

l

Faster or Slower

PTOT = (PAT + PKE + PRR + PWB + PPE)/Ec

PTOT = (0.5ρVa2Vg(CdA + Fw) + 0.5(mt + I/r2)(Vgf

2 - Vgi2)/(tf - ti) + VgCrrmtgCOS(TAN-

1(Gr)) + Vg(0.091+0.0087Vg) + VgmtgSIN(TAN-1(Gr)))/Ec

Where: PTOT = total power required (W) mt= total mass of bike+rider 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)

ρ = 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 bike+rider system (m2) Ec = efficiency of chain drive system (unitless)

FW = wheel rotation factor (expressed as incremental frontal area) (m2)

Mathematical model of the physics of cycling

(Martin, Milliken, Cobb, McFadden, and Coggan. J Appl Biomech 14:276-291, 1998)

Validation of modelunder steady-state conditions

(Martin, Milliken, Cobb, McFadden, and Coggan. J Appl Biomech 14:276-291, 1998)

Validation of modelunder non-steady-state conditions

(Martin, Gardner, Barras, and Martin, unpublished observations)

Measured power

Measured speed

Model-predicted speed

Nominal characteristics of world class pursuiters used in modeling

• 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

Male Female

• Weight of bicycle, etc. = 9.0 kg

• CRR = 0.002 (i.e., wood track)

• Air density = 1.185 g/L

Absolute and relative power requirementsof world class pursuit performance

0

100

200

300

400

500

600

Male (4 km) Female (3 km)

Po

we

r (W

)

Aerodynamic drag Kinetic energy Rolling resistance Drivetrain friction

86%

84%

7%

9%

5%

5%

2%

2%

Time savings resulting from 5% changes in:

Factor 4 km 3 km

Efficiency of chain (Ec)

0.1 s (0.05%) 0.1 s (0.05%)

Rolling resistance (CRR)

0.2 s (0.1%) 0.2 s (0.1%)

Total mass (mt)

0.6 s (0.3%) 0.6 s (0.3%)

Aerodynamic drag (CdA) 4.1 s (1.5% ) 3.1 s (1.4% )

Aerodynamics: the devil is in the details!

Field testing using a powermeter to determine aerodynamic drag characteristics (CdA)

0

100

200

300

400

0 5 10 15

Speed (m/s)

Pow

er (

W)

Westbound Eastbound line of best fit

Y = 3.67X + 0.1344X3

R2 = 0.998

CdA = 0.226 +/- 0.004 m2

CRR = 0.0046 +/- 0.0003

Technical factors

The pursuit performance ‘teeter-totter’

Neuromuscular power

Anaerobic capacity

Aerobic power

Factors

Start

Line

PacingTec

hnica

l Factors

Rolling resistance/chain friction

Inertia/kinetic energy

Aerodynamic drag

Phys

ical

Faster F

aste

rFactors

Phys

iolo

gica

l

Faster or Slower

Time savings resulting from improvements in:

Factor 4 km 3 km

Starting technique (negligible) (negligible)

Path on track (20 cm up from black line)

1.3 s (0.5%) 1.1 s (0.5%)

Pacing strategy (potentially large) (potentially large)

2005 World Championships - 3 km pursuit

70

72

74

76

78

80

82

84

86

1 2 3

Kilometer split

Tim

e (s

econ

ds)

Effect of pacing on 3 km pursuit performance

0

100

200

300

400

500

600

700

800

900

1000

0 30 60 90 120 150 180 210 240

Time (seconds)

Po

we

r (W

)

0

2

4

6

8

10

12

14

16

Sp

eed

(m

/s)

Qualifying power Final power Qualifying speed Final speed

Effect of pacing on 3 km pursuit performancewhen overall average power is equivalent

Average = 411 W

Average = 408 W

Time = 3:53.4

Time = 3:51.4

Coggan’s #1 rule of pursuiting:

Don’t go out too hard!

Don’t go out too hard!

Don’t go out too hard!

Don’t go out too hard!

Physiological factors

The pursuit performance ‘teeter-totter’

Neuromuscular power

Anaerobic capacity

Aerobic power

Factors

Start

Line

PacingTec

hnica

l Factors

Rolling resistance/chain friction

Inertia/kinetic energy

Aerodynamic drag

Phys

ical

Faster F

aste

rFactors

Phys

iolo

gica

l

Faster or Slower

The individual pursuit: a predominantly aerobic event

4 km

3 km

Energy demands expressed in O2 equivalents

Power-VO2 relationship (efficiency)

Efficiency = 24.1%

0

1

2

3

4

5

0 50 100 150 200 250 300 350 400

Power (W)

VO

2 (L

/min

)

Time savings resulting from 5% changes in:

Factor 4 km 3 km

Neuromuscular (anaerobic) power

0.3 s (0.1%) 0.2 s (0.1%)

Anaerobic capacity 0.9 s (0.3%) 0.7 s (0.3%)

Aerobic power 3.8 s (1.4%) 3.0 s (1.4%)

Role of VO2max, anaerobic capacity (MAOD) and aerodynamic drag characteristics (CdA) in determining

3 km pursuit performance

0

100

200

300

400

500

600

700

800

900

0 30 60 90 120 150 180 210 240

Time (seconds)

Pow

er (W

)

Rider A Rider B

Maximal aerobic

VO2max = 4.47 L/min

Efficiency = 24.1%

Est. MAOD = 3.36 L

Ave. power = 397 W

CdA = 0.214 m2

3 km time = 3:47.3

Total

80%

20%

Rider A

0

100

200

300

400

500

600

700

800

900

0 30 60 90 120 150 180 210 240

Time (seconds)

Pow

er (W

)

0

100

200

300

400

500

600

700

800

900

0 30 60 90 120 150 180 210 240

Time (seconds)

Po

we

r (W

)

Role of VO2max, anaerobic capacity (MAOD) and aerodynamic drag characteristics (CdA) in determining

3 km pursuit performanceRider 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 = 3:49.7

Total

Maximal aerobic72%

28%

Maximal aerobic

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 = 3:47.3

Total

80%

20%

Rider A Rider B

Preparation

Level 1 2 3 4 5 6 7

Active recovery

EnduranceTempo or

fartlekLactate

thresholdVO2max Anaerobic

capacity

Neuro-muscular

power

Power ( % of maximal steady

state)<55% 56-75% 76-90% 91-105% 106-120% 121-150% >151%

Muscle enzymes

++ +++ ++++ ++ +

Lactate threshold

++ +++ ++++ ++ +

Capillaries + ++ +++ ++++ +

Plasma volume + ++ +++ ++++ +

Stroke volume & maximal

cardiac output+ ++ +++ ++++ +

VO2max + ++ +++ ++++ +

Anaerobic capacity (MAOD)

+ +++ +

Neuromuscular power

+ +++

Expected physiological adaptationsas a function of training intensity

0

10

20

30

40

50

60

70

80

90

100

40 50 60 70 80 90 100 110 120 130 140 150

Exercise intensity (% of maximal steady state power)

Arb

itra

ry u

nit

s

L1 L2 L3 L4 L5 L6

Physiological strainOverall training effect

(increase in aerobic fitness)

Max. volume

Proposed relationship between training intensity and overall aerobic training effect

0

10

20

30

40

50

60

70

80

90

100

Month

Tra

inin

g v

olu

me

(h/m

o)

Training volume (hours/month)

LT focus (off-season “build”)

VO2max focus (road racing season)

Pursuit-specific training R&R

Day Training

Monday 1 h 30 min recovery ride

Tuesday 2 h w/ 2 x 20 min @ TT effort

Wednesday 2 h 30 min group ride at moderate intensity

Thursday 2 h w/ 2 x 20 min @ TT effort

Friday 1 h 30 min recovery ride

Saturday 4 h hard group ride

Sunday 3 h 15 min group ride at moderate intensity

Typical week during LT focus

Typical week during VO2max focus

Day Training

Monday 1 h 15 min recovery ride

Tuesday 1 h 30 min w/ 6 x 5 min at 90+% of VO2max

Wednesday 2 h at moderate intensity

Thursday 1 h 30 min w/ 6 x 5 min at 90+% of VO2max

Friday 1 h 15 h recovery ride

Saturday Race or tempo ride

Sunday Race or hard group ride

Day Training

Monday 1 h 30 min w/ 4 x 500 m flying and 10 standing starts

TuesdayAM: 1 h 30 min w/ 4 x 4 km flying in team pursuit

formation

PM: 1 h 45 min recovery ride (road)

WednesdayAM: 1 h w/ 1 x 333.3 m standing plus 3 x 1 km

standing

PM: 2 h recovery ride (road)

ThursdayAM: 1 h 30 min w/ 4 x 4 km flying in team pursuit

formation

PM: 30 min recovery ride (rollers)

FridayAM: 2 h recovery ride (road)

PM: 1 h 45 min track racing session (keirin heat, keirn final, prime race, points race)

Saturday 1 h 30 min w/ 3 x 1 km flying and 4 x 500 m flying

Sunday Off

Typical week during pursuit-specific training

0

20

40

60

80

100

120

140

160

180

200

Date

CT

L o

r A

TL

(T

SS

/d)

-100-80-60-40-20020406080100

TS

B (

TS

S/d

)

Acute training load Chronic training load Training stess balance

Use of powermeter data to manage training and plan peak performance

A happy ending!