D. H. Paterson

Run Sprint Interval Training Improves Aerobic Performance but Not Maximal Cardiac Output

UNLABELLEDnRepeated maximal-intensity short-duration exercise (sprint interval training, SIT) can produce muscle adaptations similar to endurance training (ET) despite a much reduced training volume. However, most SIT data use cycling, and little is known about its effects on body composition or maximal cardiac output (Qmax).nnnPURPOSEnThe purpose of this study was to assess body composition, 2000-m run time trial, VO(2max), and Q(max) effects of run SIT versus ET.nnnMETHODSnMen and women (n = 10 per group; mean ± SD: age = 24 ± 3 yr) trained three times per week for 6 wk with SIT, 30-s all-out run sprints (manually driven treadmill), four to six bouts per session, 4-min recovery per bout, versus ET, 65% VO(2max) for 30 to 60 min·d(-1).nnnRESULTSnTraining improved (P < 0.05) body composition, 2000-m run time trial performance, and VO(2max) in both groups. Fat mass decreased 12.4% with SIT (mean ± SEM; 13.7 ± 1.6 to 12.0 ± 1.6 kg) and 5.8% with ET (13.9 ± 1.7 to 13.1 ± 1.6 kg). Lean mass increased 1% in both groups. Time trial performance improved 4.6% with SIT (-25.6 ± 8.1 s) and 5.9% with ET (-31.9 ± 6.3 s). VO(2max) increased 11.5% with SIT (46.8 ± 1.6 to 52.2 ± 2.0 mL·kg·(-1)·min(-1)) and 12.5% with ET (44.0 ± 2.0 to 49.5 ± 2.6 mL·kg·(-1)·min(-1)). None of these improvements differed between groups. In contrast, Q(max) increased by 9.5% with ET only (22.2 ± 2.0 to 24.3 ± 1.6 L·min(-1)).nnnCONCLUSIONSnDespite a fraction of the time commitment, run SIT induces similar body composition, VO(2max), and performance adaptations as ET, but with no effect on Q(max). These data suggest that adaptations with ET are of central origin primarily, whereas those with SIT are more peripheral

Physiological responses of young and elderly men to prolonged exercise at critical power

SummaryThe critical power (CP) of a muscle group or individual may represent the highest rate of work which can be performed for an extended period. We investigated this concept in young (n = 13, 24.5 years) and elderly (n = 12, 70.7 years) active men by first determining CP and then comparing responses elicited by 24 min of cycle exercise at power outputs (ω) corresponding to CP. Values from the final 2 min of the 24-min ride were expressed relative to maximal values established in a ramp test. CP for the elderly was only 65% that for the young, but on a relative basis, it was significantly higher both in terms of ω (67 vs 62% of ωmax) and oxygen consumption (n

The effects of age on kinetics of oxygen uptake and phosphocreatine in humans during exercise

dot VO_2

Nature of the interaction between central and peripheral chemoreceptor drives in human subjects.

n) (91.5 vs 85.2% of maximum oxygen consumption). There were no group differences in relative values for ventilation (n

The Off‐Transient Pulmonary Oxygen Uptake (VO2) Kinetics Following Attainment of a Particular VO2 During Heavy‐Intensity Exercise in Humans

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The Effects of Caffeine on the Kinetics of O2Uptake, CO2Production and Expiratory Ventilation in Humans During the On-Transient of Moderate and Heavy Intensity Exercise

n), heart rate or respiratory exchange ratio (R). During the 24-min ride,n