Influence of Continuous and Interval Training on Oxygen Uptake On-Kinetics

BERGER, NICOLAS J. A.; TOLFREY, KEITH; WILLIAMS, ALUN G.; JONES, ANDREW M.

Medicine & Science in Sports & Exercise: March 2006 - Volume 38 - Issue 3 - pp 504-512
doi: 10.1249/01.mss.0000191418.37709.81
BASIC SCIENCES: Original Investigations

Purpose: To examine the relative effectiveness of moderate-intensity continuous training and high-intensity interval training on pulmonary O2 uptake (V̇O2) kinetics at the onset of moderate- and severe-intensity cycle exercise in previously sedentary subjects.

Methods: Twenty-three healthy subjects (11 males; mean ± SD age 24 ± 5 yr; V̇O2peak 34.3 ± 5.5 mL·kg−1·min−1) were assigned to one of three groups: a continuous training group that completed three to four sessions per week of 30-min duration at 60% V̇O2peak (LO); an interval training group that completed three to four sessions per week involving 20 × 1-min exercise bouts at 90% V̇O2peak separated by 1-min rest periods (HI); or a control group (CON). Before and after the 6-wk intervention period, all subjects completed a series of step exercise tests to moderate and severe work rates during which pulmonary V̇O2 was measured breath-by-breath.

Results: ANOVA revealed that continuous and interval training were similarly effective in reducing the phase II V̇O2 time constant during moderate (LO: from 31 ± 8 to 23 ± 5 s; HI: from 32 ± 9 to 21 ± 4 s; both P < 0.05; CON: from 30 ± 6 to 29 ± 7 s; NSD) and severe exercise (LO: from 35 ± 6 to 24 ± 7 s; HI: from 32 ± 11 to 24 ± 7 s; both P < 0.05; CON: from 27 ± 7 to 25 ± 5 s; NSD) and in reducing the amplitude of the V̇O2 slow component (LO: from 0.38 ± 0.10 to 0.29 ± 0.09 L·min−1; HI: from 0.41 ± 0.28 to 0.30 ± 0.28 L·min−1; both P < 0.05; CON: from 0.54 ± 0.22 to 0.66 ± 0.38 L·min−1; NSD).

Conclusions: Six weeks of low-intensity continuous training and high-intensity interval training were similarly effective in enhancing V̇O2 on-kinetics following step transitions to moderate and severe exercise in previously untrained subjects.

Department of Exercise and Sport Science, Manchester Metropolitan University, Hassall Road, Alsager, UNITED KINGDOM

Address for correspondence: Professor A. M. Jones, School of Sport and Health Sciences, University of Exeter, Exeter EX1 2LU, United Kingdom; E-mail: a.m.jones@exeter.ac.uk.

Submitted for publication March 2005.

Accepted for publication October 2005.

©2006The American College of Sports Medicine