Influence of duty cycle on the power-duration relationship: observations and potential mechanisms

Respiratory Physiology & Neurobiology
R M BroxtermanT J Barstow

Abstract

The highest sustainable rate of aerobic metabolism [critical power (CP)] and the finite amount of work that can be performed above CP (W' [curvature constant]) were determined under two muscle contraction duty cycles. Eight men completed at least three constant-power handgrip tests to exhaustion to determine CP and W' for 50% and 20% duty cycles, while brachial artery blood flow (Q̇BA) and deoxygenated-[hemoglobin + myoglobin] (deoxy-[Hb+Mb]) were measured. CP was lower for the 50% duty cycle (3.9 ± 0.9 W) than the 20% duty cycle (5.1 ± 0.8 W; p < 0.001), while W' was not significantly different (50% duty cycle: 452 ± 141 J vs. 20% duty cycle: 432 ± 130 J; p > 0.05). At the same power output, Q̇BA and deoxy-[Hb + Mb] achieved higher end-exercise values for the 20% duty cycle (9.87 ± 1.73 ml·s(-1); 51.7 ± 4.7 μM) than the 50% duty cycle (7.37 ± 1.76 ml·s(-1), p < 0.001; 44.3 ± 2.4 μM, p < 0.03). These findings indicate that blood flow influences CP, but not W'.

References

Apr 12, 1979·European Journal of Applied Physiology and Occupational Physiology·J S Petrofsky
Nov 1, 1992·Medicine and Science in Sports and Exercise·D G Jenkins, B M Quigley
Feb 1, 1991·Medicine and Science in Sports and Exercise·T J Carnevale, G A Gaesser
Jan 1, 1973·Journal of the Neurological Sciences·M A JohnsonD Appleton
Sep 1, 1970·Acta Physiologica Scandinavica·B FolkowB A Waaler
Jan 1, 1983·European Journal of Applied Physiology and Occupational Physiology·T SadamotoY Suzuki
Feb 1, 1995·International Journal of Sports Medicine·D W HillS A Miller
Apr 1, 1994·International Journal of Sports Medicine·A J Sargeant
Oct 1, 1993·Sports Medicine·D W Hill
Jan 1, 1993·European Journal of Applied Physiology and Occupational Physiology·R A De BlasiM Ferrari
Feb 1, 1993·Medicine and Science in Sports and Exercise·D G Jenkins, B M Quigley
May 1, 1996·International Journal of Sports Medicine·L McNaughton, D Thomas
Jun 29, 1997·Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences·M FerrariV Quaresima
Jun 29, 1997·Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences·E GrattonM Fabiani
Apr 30, 1998·European Journal of Applied Physiology and Occupational Physiology·J C SmithC P Earnest
Oct 17, 1998·British Journal of Sports Medicine·B J WhippM W Hassall
Sep 5, 2001·Journal of Electromyography and Kinesiology : Official Journal of the International Society of Electrophysiological Kinesiology·S R PerryK T Ebersole
Jan 15, 2002·American Journal of Physiology. Endocrinology and Metabolism·David W RussStuart A Binder-Macleod
Feb 14, 2002·Journal of Applied Physiology·Takuya Osada, Göran Rådegran
May 17, 2002·Journal of Applied Physiology·Casey A KindigDavid C Poole
Oct 17, 2002·Journal of Applied Physiology·Gisela SjøgaardTakuya Osada
Apr 1, 2003·Journal of Applied Physiology·Edward M CoatsBrian J Whipp
Aug 6, 2003·Medicine and Science in Sports and Exercise·Yoshiyuki FukubaBrian J Whipp
Dec 4, 2003·Medicine and Science in Sports and Exercise·Andrew M JonesKatrien Koppo
Jul 1, 1952·The Journal of Physiology·B C ABBOTTJ M RITCHIE
Sep 1, 1949·The Journal of Physiology·H BARCROFT, A C DORNHORST
Nov 24, 2004·Journal of Applied Physiology·Barbara J LutjemeierThomas J Barstow
Feb 5, 2005·Journal of Applied Physiology·Jason J HamannPhilip S Clifford
Oct 1, 2005·International Journal of Sports Medicine·R A P HeubertP E di Prampero
Dec 22, 2005·European Journal of Applied Physiology·Leonardo F FerreiraThomas J Barstow
Mar 11, 2006·Experimental Physiology·Tyler BarkerThomas J Barstow
Dec 7, 2007·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Andrew M JonesDavid C Poole
Dec 29, 2007·Journal of Applied Physiology·Robert H Fitts
Aug 8, 2008·Medicine and Science in Sports and Exercise·Anni VanhataloMark Burnley
Oct 9, 2009·European Journal of Applied Physiology·Clayton L CamicRichard J Schmidt
Mar 3, 2010·Medicine and Science in Sports and Exercise·Andrew M JonesDavid C Poole
May 21, 2010·Computer Methods and Programs in Biomedicine·Peter D Wagner
Dec 17, 2010·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Anni VanhataloAndrew M Jones
Mar 19, 2011·Journal of Applied Physiology·Scott R MurgatroydHarry B Rossiter
Apr 20, 2011·Medicine and Science in Sports and Exercise·Markus Amann

❮ Previous
Next ❯

Citations

Oct 14, 2014·European Journal of Sport Science·R M BroxtermanT J Barstow
Dec 20, 2014·Respiratory Physiology & Neurobiology·R M BroxtermanT J Barstow
Oct 19, 2016·Medicine and Science in Sports and Exercise·David C PooleAndrew M Jones
Apr 13, 2018·The Journal of Physiology·Ryan M BroxtermanRussell S Richardson
Feb 13, 2018·Medicine and Science in Sports and Exercise·Ted PolglazePeter Peeling
Mar 2, 2018·Journal of Applied Physiology·Christopher W SundbergSandra K Hunter
Mar 8, 2019·Journal of Applied Physiology·Thomas J Barstow
May 6, 2019·Experimental Physiology·Richie P GouldingSimon Marwood
Apr 17, 2015·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Christopher W Sundberg, Matthew W Bundle
Nov 15, 2019·Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquée, Nutrition Et Métabolisme·Jacob T CaldwellCarl J Ade
May 28, 2019·Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquée, Nutrition Et Métabolisme·Tatiane PiuccoRicardo Dantas de Lucas
Nov 13, 2019·Experimental Physiology·Kaylin D DidierThomas J Barstow
Jan 25, 2020·The Journal of Physiology·David C PooleTimothy I Musch
Dec 10, 2019·Medicine and Science in Sports and Exercise·Richie P GouldingSimon Marwood
Nov 9, 2016·Aging·Gwenael LayecRussell S Richardson
Nov 21, 2019·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Wesley J TuckerMichael D Nelson
Nov 14, 2015·Journal of Applied Physiology·Carrie FergusonHarry B Rossiter
Mar 16, 2017·American Journal of Physiology. Endocrinology and Metabolism·Gwenael LayecRussell S Richardson
Aug 1, 2015·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Ryan M BroxtermanThomas J Barstow
Apr 12, 2020·European Journal of Applied Physiology·Johannes L Herold, Andreas Sommer
May 4, 2018·European Journal of Applied Physiology·Natalie R JanzenChristopher D Black
Mar 3, 2019·Physiological Reports·Andrew M AlexanderThomas J Barstow
Nov 10, 2020·Frontiers in Physiology·Jean Romain RivièrePierre Samozino
Jun 15, 2021·Respiratory Physiology & Neurobiology·Shane M HammerCarl J Ade

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Related Papers

Medicine and Science in Sports and Exercise
Brandon J SawyerG A Gaesser
The Annals of Physiological Anthropology = Seiri Jinruigaku Kenkyūkai Kaishi
C LeeY Kikuchi
© 2021 Meta ULC. All rights reserved