Tasuku Terada1, Saeed R Toghi Eshghi2, Yilina Liubaoerjijin2, Michael Kennedy2, Étienne Myette-Côté3, Kevin Fletcher2, Normand G Boulé4. 1. Department of Occupational Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada. 2. Faculty of Kinesiology, Sport and Recreation. 3. -052 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, Canada. 4. Faculty of Kinesiology, Sport and Recreation - nboule@ualberta.ca.
Abstract
BACKGROUND: The combined effects of sprint interval training (SIT) and exercising in the fasted state are unknown. We compared the effects of SIT with exogenous carbohydrate supplementation (SIT-CHO) and SIT following overnight fast (SIT-Fast) on aerobic capacity (peak oxygen consumption: V̇O2peak) and high-intensity aerobic endurance (time-to-exhaustion at 85% V̇O2peak [T85%]). METHODS:Twenty male cyclists were randomized to SIT-CHO and SIT-Fast. Both groups performed 30-second all-out cycling followed by 4-minute active recovery 3 times per week for 4 weeks, with the number of sprint bouts progressing from 4 to 7. Peak power output (PPO) and total mechanical work were measured for each sprint interval bout. The SIT-CHO group performed exercise sessions following breakfast and consumed carbohydrate drink during exercise, whereas the SIT-Fast group performed exercise sessions following overnight fast and consumed water during exercise. Before and after training, V̇O2peak and T85% were assessed. Blood glucose, non-esterifiedfatty acids, insulin and glucagon concentrations were measured during T85%. RESULTS:Overall PPO and mechanical work were lower in SIT-Fast than SIT-CHO (3664.9 vs. 3871.7 J/kg; P=0.021 and 10.6 vs. 9.9 W/kg; P=0.010, respectively). Post-training V̇O2peak did not differ between groups. Baseline-adjusted post-training T85% was longer in SIT-Fast compared to SIT-CHO (19.7±3.0 vs. 16.6±3.0 minutes, ANCOVA P=0.038) despite no changes in circulating energy substrates or hormones. CONCLUSIONS: Our results suggest that SIT-Fast compromises exercise intensity and volume but still can have a greater impact on the ability to sustain high-intensity aerobic endurance exercise compared to SIT-CHO.
RCT Entities:
BACKGROUND: The combined effects of sprint interval training (SIT) and exercising in the fasted state are unknown. We compared the effects of SIT with exogenous carbohydrate supplementation (SIT-CHO) and SIT following overnight fast (SIT-Fast) on aerobic capacity (peak oxygen consumption: V̇O2peak) and high-intensity aerobic endurance (time-to-exhaustion at 85% V̇O2peak [T85%]). METHODS: Twenty male cyclists were randomized to SIT-CHO and SIT-Fast. Both groups performed 30-second all-out cycling followed by 4-minute active recovery 3 times per week for 4 weeks, with the number of sprint bouts progressing from 4 to 7. Peak power output (PPO) and total mechanical work were measured for each sprint interval bout. The SIT-CHO group performed exercise sessions following breakfast and consumed carbohydrate drink during exercise, whereas the SIT-Fast group performed exercise sessions following overnight fast and consumed water during exercise. Before and after training, V̇O2peak and T85% were assessed. Blood glucose, non-esterified fatty acids, insulin and glucagon concentrations were measured during T85%. RESULTS: Overall PPO and mechanical work were lower in SIT-Fast than SIT-CHO (3664.9 vs. 3871.7 J/kg; P=0.021 and 10.6 vs. 9.9 W/kg; P=0.010, respectively). Post-training V̇O2peak did not differ between groups. Baseline-adjusted post-training T85% was longer in SIT-Fast compared to SIT-CHO (19.7±3.0 vs. 16.6±3.0 minutes, ANCOVA P=0.038) despite no changes in circulating energy substrates or hormones. CONCLUSIONS: Our results suggest that SIT-Fast compromises exercise intensity and volume but still can have a greater impact on the ability to sustain high-intensity aerobic endurance exercise compared to SIT-CHO.
Authors: Scott C Forbes; Darren G Candow; Abbie E Smith-Ryan; Katie R Hirsch; Michael D Roberts; Trisha A VanDusseldorp; Matthew T Stratton; Mojtaba Kaviani; Jonathan P Little Journal: Nutrients Date: 2020-01-31 Impact factor: 5.717
Authors: J Javier Perez-Montilla; Maria Cuevas-Cervera; Ana Gonzalez-Muñoz; Maria Carmen Garcia-Rios; Santiago Navarro-Ledesma Journal: Int J Environ Res Public Health Date: 2022-04-01 Impact factor: 3.390
Authors: Todd A Astorino; Sarah Sherrick; Monique Mariscal; Vianney Camarillo Jimenez; Kelli Stetson; Daniel Courtney Journal: Biol Sport Date: 2019-05-30 Impact factor: 2.806