Cardiorespiratory fitness and aerobic performance adaptations to a 4-week sprint interval training in young healthy untrained females
Question
Can 4 weeks of low-volume cycling sprint interval training improve cardiorespiratory fitness and aerobic performance in young untrained women?
Summary
Eight healthy untrained young women completed eight cycling sprint-interval sessions over 4 weeks. The 4 x 30 s all-out protocol improved time to exhaustion, 10 km cycling time-trial performance, critical power, and training peak-power output, but it did not significantly improve peak oxygen uptake.
Methodology
- Eight healthy untrained young women.
- 8 participants.
- Cycle ergometer.
- Work intervals: 30 s.
- Recovery: 4 min low-cadence unloaded cycling.
- Intensity: All-out against 7% body mass.
- About 14 min sprint/recovery block.
- 2 sessions/week.
- 4 weeks.
- Single-group repeated-measures intervention with a 4-week control period
- VO2peak, and Aerobic performance were tracked.
Outcomes
TTE
Time to exhaustion improved after SIT.
+12 +/- 4%, p=0.001.
10 km TT
10 km cycling time trial was faster after SIT.
-6 +/- 4%, p=0.004.
VO2peak
VO2peak did not significantly change after eight SIT sessions.
Pre-SIT-2 31.7 +/- 3.0 vs post-SIT 30.9 +/- 4.5 ml/kg/min; p>0.05.
Insights
- Very short all-out sprint blocks may improve cycling performance even without VO2peak gains.
- Twice-weekly SIT may be below the dose needed for cardiorespiratory-fitness improvement.
Limitations
- Small sample
- No parallel control group
- Women only
- Diet and outside exercise not monitored
- Short intervention
Safety
- No adverse events or injuries were reported.