Prediction of critical power and W' in hypoxia: Application to work-balance modelling

Nathan E Townsend, David S Nichols, Philip F Skiba, Sebastien Racinais, J.D. Périard

Research output: Contribution to journalArticle

6 Citations (Scopus)
2 Downloads (Pure)

Abstract

Purpose: Develop a prediction equation for critical power (CP) and work above CP (W') in hypoxia for use in the work-balance (WBAL') model. Methods: Nine trained male cyclists completed cycling time trials (TT; 12, 7, and 3 min) to determine CP and W' at five altitudes (250, 1,250, 2,250, 3,250, and 4,250 m). Least squares regression was used to predict CP and W' at altitude. A high-intensity intermittent test (HIIT) was performed at 250 and 2,250 m. Actual and predicted CP and W' were used to compute W' during HIIT using differential (WBALdiff') and integral (WBALint') forms of the WBAL' model. Results: CP decreased at altitude (P < 0.001) as described by 3rd order polynomial function (R2 = 0.99). W' decreased at 4,250 m only (P < 0.001). A double-linear function characterized the effect of altitude on W' (R2 = 0.99). There was no significant effect of parameter input (actual vs. predicted CP and W') on modelled WBAL' at 2,250 m (P = 0.24). WBALdiff' returned higher values than WBALint' throughout HIIT (P < 0.001). During HIIT, WBALdiff' was not different to 0 kJ at completion, at 250 m (0.7 ± 2.0 kJ; P = 0.33) and 2,250 m (-1.3 ± 3.5 kJ; P = 0.30). However, WBALint' was lower than 0 kJ at 250 m (-0.9 ± 1.3 kJ; P = 0.058) and 2,250 m (-2.8 ± 2.8 kJ; P = 0.02). Conclusion: The altitude prediction equations for CP and W' developed in this study are suitable for use with the WBAL' model in acute hypoxia. This enables the application of WBAL' modelling to training prescription and competition analysis at altitude.

Original languageEnglish
Article number180
JournalFrontiers in Physiology
Volume8
Issue numberMAR
DOIs
Publication statusPublished - 23 Mar 2017
Externally publishedYes

Fingerprint

Least-Squares Analysis
Prescriptions
Hypoxia

Cite this

Townsend, Nathan E ; Nichols, David S ; Skiba, Philip F ; Racinais, Sebastien ; Périard, J.D. / Prediction of critical power and W' in hypoxia: Application to work-balance modelling. In: Frontiers in Physiology. 2017 ; Vol. 8, No. MAR.
@article{16d398921fe545feb1d7318547563f5d,
title = "Prediction of critical power and W' in hypoxia: Application to work-balance modelling",
abstract = "Purpose: Develop a prediction equation for critical power (CP) and work above CP (W') in hypoxia for use in the work-balance (WBAL') model. Methods: Nine trained male cyclists completed cycling time trials (TT; 12, 7, and 3 min) to determine CP and W' at five altitudes (250, 1,250, 2,250, 3,250, and 4,250 m). Least squares regression was used to predict CP and W' at altitude. A high-intensity intermittent test (HIIT) was performed at 250 and 2,250 m. Actual and predicted CP and W' were used to compute W' during HIIT using differential (WBALdiff') and integral (WBALint') forms of the WBAL' model. Results: CP decreased at altitude (P < 0.001) as described by 3rd order polynomial function (R2 = 0.99). W' decreased at 4,250 m only (P < 0.001). A double-linear function characterized the effect of altitude on W' (R2 = 0.99). There was no significant effect of parameter input (actual vs. predicted CP and W') on modelled WBAL' at 2,250 m (P = 0.24). WBALdiff' returned higher values than WBALint' throughout HIIT (P < 0.001). During HIIT, WBALdiff' was not different to 0 kJ at completion, at 250 m (0.7 ± 2.0 kJ; P = 0.33) and 2,250 m (-1.3 ± 3.5 kJ; P = 0.30). However, WBALint' was lower than 0 kJ at 250 m (-0.9 ± 1.3 kJ; P = 0.058) and 2,250 m (-2.8 ± 2.8 kJ; P = 0.02). Conclusion: The altitude prediction equations for CP and W' developed in this study are suitable for use with the WBAL' model in acute hypoxia. This enables the application of WBAL' modelling to training prescription and competition analysis at altitude.",
keywords = "Altitude, Cycling, Fatigue, High-intensity intermittent exercise, Hypoxia",
author = "Townsend, {Nathan E} and Nichols, {David S} and Skiba, {Philip F} and Sebastien Racinais and J.D. P{\'e}riard",
note = "Export Date: 23 May 2017",
year = "2017",
month = "3",
day = "23",
doi = "10.3389/fphys.2017.00180",
language = "English",
volume = "8",
journal = "Frontiers in Physiology",
issn = "1664-042X",
publisher = "Frontiers Media S.A.",
number = "MAR",

}

Prediction of critical power and W' in hypoxia: Application to work-balance modelling. / Townsend, Nathan E; Nichols, David S; Skiba, Philip F; Racinais, Sebastien; Périard, J.D.

In: Frontiers in Physiology, Vol. 8, No. MAR, 180, 23.03.2017.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Prediction of critical power and W' in hypoxia: Application to work-balance modelling

AU - Townsend, Nathan E

AU - Nichols, David S

AU - Skiba, Philip F

AU - Racinais, Sebastien

AU - Périard, J.D.

N1 - Export Date: 23 May 2017

PY - 2017/3/23

Y1 - 2017/3/23

N2 - Purpose: Develop a prediction equation for critical power (CP) and work above CP (W') in hypoxia for use in the work-balance (WBAL') model. Methods: Nine trained male cyclists completed cycling time trials (TT; 12, 7, and 3 min) to determine CP and W' at five altitudes (250, 1,250, 2,250, 3,250, and 4,250 m). Least squares regression was used to predict CP and W' at altitude. A high-intensity intermittent test (HIIT) was performed at 250 and 2,250 m. Actual and predicted CP and W' were used to compute W' during HIIT using differential (WBALdiff') and integral (WBALint') forms of the WBAL' model. Results: CP decreased at altitude (P < 0.001) as described by 3rd order polynomial function (R2 = 0.99). W' decreased at 4,250 m only (P < 0.001). A double-linear function characterized the effect of altitude on W' (R2 = 0.99). There was no significant effect of parameter input (actual vs. predicted CP and W') on modelled WBAL' at 2,250 m (P = 0.24). WBALdiff' returned higher values than WBALint' throughout HIIT (P < 0.001). During HIIT, WBALdiff' was not different to 0 kJ at completion, at 250 m (0.7 ± 2.0 kJ; P = 0.33) and 2,250 m (-1.3 ± 3.5 kJ; P = 0.30). However, WBALint' was lower than 0 kJ at 250 m (-0.9 ± 1.3 kJ; P = 0.058) and 2,250 m (-2.8 ± 2.8 kJ; P = 0.02). Conclusion: The altitude prediction equations for CP and W' developed in this study are suitable for use with the WBAL' model in acute hypoxia. This enables the application of WBAL' modelling to training prescription and competition analysis at altitude.

AB - Purpose: Develop a prediction equation for critical power (CP) and work above CP (W') in hypoxia for use in the work-balance (WBAL') model. Methods: Nine trained male cyclists completed cycling time trials (TT; 12, 7, and 3 min) to determine CP and W' at five altitudes (250, 1,250, 2,250, 3,250, and 4,250 m). Least squares regression was used to predict CP and W' at altitude. A high-intensity intermittent test (HIIT) was performed at 250 and 2,250 m. Actual and predicted CP and W' were used to compute W' during HIIT using differential (WBALdiff') and integral (WBALint') forms of the WBAL' model. Results: CP decreased at altitude (P < 0.001) as described by 3rd order polynomial function (R2 = 0.99). W' decreased at 4,250 m only (P < 0.001). A double-linear function characterized the effect of altitude on W' (R2 = 0.99). There was no significant effect of parameter input (actual vs. predicted CP and W') on modelled WBAL' at 2,250 m (P = 0.24). WBALdiff' returned higher values than WBALint' throughout HIIT (P < 0.001). During HIIT, WBALdiff' was not different to 0 kJ at completion, at 250 m (0.7 ± 2.0 kJ; P = 0.33) and 2,250 m (-1.3 ± 3.5 kJ; P = 0.30). However, WBALint' was lower than 0 kJ at 250 m (-0.9 ± 1.3 kJ; P = 0.058) and 2,250 m (-2.8 ± 2.8 kJ; P = 0.02). Conclusion: The altitude prediction equations for CP and W' developed in this study are suitable for use with the WBAL' model in acute hypoxia. This enables the application of WBAL' modelling to training prescription and competition analysis at altitude.

KW - Altitude

KW - Cycling

KW - Fatigue

KW - High-intensity intermittent exercise

KW - Hypoxia

UR - http://www.scopus.com/inward/record.url?scp=85016138327&partnerID=8YFLogxK

UR - http://www.mendeley.com/research/prediction-critical-power-w-hypoxia-application-workbalance-modelling

U2 - 10.3389/fphys.2017.00180

DO - 10.3389/fphys.2017.00180

M3 - Article

VL - 8

JO - Frontiers in Physiology

JF - Frontiers in Physiology

SN - 1664-042X

IS - MAR

M1 - 180

ER -