title: Physiological responses during interval training with different intensities and duration of exercise.
abstract: The purpose of this study was to compare 4 interval training (IT) sessions with different intensities and durations of exercise to determine the effect on mean VO₂, total VO₂, and duration of exertion ≥95% maximum power output (MPO), and the effects on biomarkers of fatigue such as blood-lactate concentration (BLC) and rating of perceived exertion. The subjects were 12 recreationally competitive male (n = 7, mean ± SD age = 26.2 ± 3.9 years) and female (n = 5, mean ± SD age = 27.6 ± 4.3 years) triathletes. These subjects performed 4 IT sessions on a cycle ergometer varying in intensity (90 and 100% MPO) and duration of exercise (30 seconds and 3 minutes). This study revealed that IT using 30-second duration intervals (30-30 seconds) allows the athlete to perform a longer session, with a higher total and mean VO₂ HR and lower BLC than 3-minute durations. Similarly, submaximal exertion at 90% of MPO also allows performing longer sessions with a higher total VO₂ than 100% intensity. Thus, the results of the present study suggested that to increase the total time at high intensity of exercise and total VO₂ of a single exercise session performed by the athlete, IT protocols of short durations (i.e., 30 seconds) and submaximal intensities (i.e., 90% MPO) should be selected. Furthermore, performing short-duration intervals may allow the athlete to complete a longer IT session with greater metabolic demands (VO₂) and lower BLC than longer (i.e., 3 minutes) intervals.
authors.affiliation: Human Performance Laboratory, Department of Nutrition and Health Sciences, Center of Youth Fitness and Sports Research, University of Nebraska Lincoln, Lincoln, Nebraska, USA. jzuniga2@unlserve.unl.edu
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Zuniga
authors.forename: Kris
authors.initials: K
authors.lastname: Berg
authors.forename: John
authors.initials: J
authors.lastname: Noble
authors.forename: Jeanette
authors.initials: J
authors.lastname: Harder
authors.forename: Morgan E
authors.initials: ME
authors.lastname: Chaffin
authors.forename: Vidya S
authors.initials: VS
authors.lastname: Hanumanthu
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D056352:Athletes / Q000706:statistics & numerical data; D015331:Cohort Studies; D004734:Energy Metabolism / Q000502:physiology; D005080:Exercise Test / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D018763:Muscle Fatigue; D010101:Oxygen Consumption / Q000502:physiology*; D010806:Physical Education and Training / Q000379:methods*; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D012680:Sensitivity and Specificity; D013997:Time Factors; D055815:Young Adult