International Journal of Sports Physiology and Performance, 2015, 10, 630 -635 http://dx.doi.org/10.1123/ijspp.2014-0218 © 2015 Human Kinetics, Inc.
ORIGINAL INVESTIGATION
Effects of Active Versus Passive Recovery in Sprint Cross-Country Skiing Thomas Losnegard, Martin Andersen, Matt Spencer, and Jostein Hallén Purpose: To investigate the effects of an active and a passive recovery protocol on physiological responses and performance between 2 heats in sprint cross-country skiing. Methods: Ten elite male skiers (22 ± 3 y, 184 ± 4 cm, 79 ± 7 kg) undertook 2 experimental test sessions that both consisted of 2 heats with 25 min between start of the first and second heats. The heats were conducted as an 800-m time trial (6°, >3.5 m/s, ~205 s) and included measurements of oxygen uptake (VO2) and accumulated oxygen deficit. The active recovery trial involved 2 min standing/walking, 16 min jogging (58% ± 5% of VO2peak), and 3 min standing/walking. The passive recovery trial involved 15 min sitting, 3 min walk/jog (~ 30% of VO2peak), and 3 min standing/ walking. Blood lactate concentration and heart rate were monitored throughout the recovery periods. Results: The increased 800-m time between heat 1 and heat 2 was trivial after active recovery (effect size [ES] = 0.1, P = .64) and small after passive recovery (ES = 0.4, P = .14). The 1.2% ± 2.1% (mean ± 90% CL) difference between protocols was not significant (ES = 0.3, P = .3). In heat 2, peak and average VO2 was increased after the active recovery protocol. Conclusions: Neither passive recovery nor running at ~58% of VO2peak between 2 heats changed performance significantly. Keywords: accumulated oxygen deficit, elite athletes, lactate reduction, repeated sprint, VO2max Sprint cross-country (XC) skiing consists of 1 time trial (prologue; interval start) and 3 knockout heats (quarterfinal, semifinal, and final races). The 30 fastest skiers qualify from the prologue, and thereafter 6 skiers compete in each heat. Semifinal and final heats include the 2 fastest racers from each quarterfinal and semifinal heat. In addition, the 2 overall fastest “lucky losers” who did not directly qualify from each quarter and semifinal heat progress to the next round. The typical heat duration for World Cup races during the past 4 seasons was ~180 seconds (range 130–210 s), whereas the recovery periods were 15 to 25 minutes between semifinal and final races.1 During these recovery periods, skiers use different strategies and different-intensity workouts with the explicit goal of maintaining performance. The ability to perform repeated sprints is likely to be influenced by the nature of the recovery strategy.2,3 Although several studies have described changes in kinematic and physiological variables with repeated, simulated sprint heats in XC skiing,4–8 surprisingly little information exists about the effect of different recovery protocols on performance. A number of studies from other sports such as swimming and cycling have demonstrated a beneficial performance effect of active recovery on subsequent exercise bouts lasting
ORIGINAL INVESTIGATION
Effects of Active Versus Passive Recovery in Sprint Cross-Country Skiing Thomas Losnegard, Martin Andersen, Matt Spencer, and Jostein Hallén Purpose: To investigate the effects of an active and a passive recovery protocol on physiological responses and performance between 2 heats in sprint cross-country skiing. Methods: Ten elite male skiers (22 ± 3 y, 184 ± 4 cm, 79 ± 7 kg) undertook 2 experimental test sessions that both consisted of 2 heats with 25 min between start of the first and second heats. The heats were conducted as an 800-m time trial (6°, >3.5 m/s, ~205 s) and included measurements of oxygen uptake (VO2) and accumulated oxygen deficit. The active recovery trial involved 2 min standing/walking, 16 min jogging (58% ± 5% of VO2peak), and 3 min standing/walking. The passive recovery trial involved 15 min sitting, 3 min walk/jog (~ 30% of VO2peak), and 3 min standing/ walking. Blood lactate concentration and heart rate were monitored throughout the recovery periods. Results: The increased 800-m time between heat 1 and heat 2 was trivial after active recovery (effect size [ES] = 0.1, P = .64) and small after passive recovery (ES = 0.4, P = .14). The 1.2% ± 2.1% (mean ± 90% CL) difference between protocols was not significant (ES = 0.3, P = .3). In heat 2, peak and average VO2 was increased after the active recovery protocol. Conclusions: Neither passive recovery nor running at ~58% of VO2peak between 2 heats changed performance significantly. Keywords: accumulated oxygen deficit, elite athletes, lactate reduction, repeated sprint, VO2max Sprint cross-country (XC) skiing consists of 1 time trial (prologue; interval start) and 3 knockout heats (quarterfinal, semifinal, and final races). The 30 fastest skiers qualify from the prologue, and thereafter 6 skiers compete in each heat. Semifinal and final heats include the 2 fastest racers from each quarterfinal and semifinal heat. In addition, the 2 overall fastest “lucky losers” who did not directly qualify from each quarter and semifinal heat progress to the next round. The typical heat duration for World Cup races during the past 4 seasons was ~180 seconds (range 130–210 s), whereas the recovery periods were 15 to 25 minutes between semifinal and final races.1 During these recovery periods, skiers use different strategies and different-intensity workouts with the explicit goal of maintaining performance. The ability to perform repeated sprints is likely to be influenced by the nature of the recovery strategy.2,3 Although several studies have described changes in kinematic and physiological variables with repeated, simulated sprint heats in XC skiing,4–8 surprisingly little information exists about the effect of different recovery protocols on performance. A number of studies from other sports such as swimming and cycling have demonstrated a beneficial performance effect of active recovery on subsequent exercise bouts lasting
