Effects of sprint interval training on maximal oxygen uptake in athletes: a meta-analysis

INTRODUCTION: To explore the effects of sprint interval training on maximal oxygen uptake (VO2max) in athletes, and whether exercise mode, number of sprints, sprint duration, and interval duration would positively impact on athletes' VO2max, so as to improve the reference of exercise prescriptions.METHODS: A comprehensive search of the literature was conducted using the key words "sprint interval training" and "maximal oxygen uptake" on databases, including both Chinese and English articles published from the establishment of the database to January 2021. The articles were selected by two independent reviewers. The quality of the included studies was evaluated in compliance with the risk-of-bias assessment tool for randomized controlled trials recommended in the Cochrane Handbook.RESULTS: After screening and exclusion, 12 studies were included in the meta analysis. VO2max in the sprint training group was significantly increased by 2.23 ml/kg/min (95% CI 0.99-3.48; p = 0.987). Subgroup analysis was conducted on exercise type, number of sprints, sprint duration, interval duration, and training period, the results of which showed that VO2max of sprinting-based group was increased by 2.43 ml/kg/min (95% CI 0.41-4.45; p = 0.987); VO2max of sprint duration group 2.27 ml/kg/min (95% CI 0.83-3.71; p = 0.96); VO2max of interval duration < 3 min group 2.39 ml/kg/min (95% CI 0.74-4.03; p = 0.92); VO2max of 8-12 sprints group 2.57 ml/kg/min (95% CI 0.75-4.38; p = 0.96); VO2max of SIT for 3-4 weeks group 2.78 ml/kg/min (95% CI 1.00-4.57; p = 0.96). The funnel plot and Egger's test did not suggest publication bias.CONCLUSIONS: (1) SIT can significantly enhance VO2max in athletes. (2) The training program of 3-week sprinting-based SIT with 8-12, 20-30s sprints and intervals less than 3 min between each sprint is the most significant in improving VO2max in athletes.