Effects of an 8-week high intensity interval training (HIIT) and ashwagandha supplementation on aerobic capacity, muscle oxygenation and haematological parameters in healthy men
Question
Does ashwagandha supplementation improve aerobic capacity, muscle oxygenation, or hematological responses during an 8-week rowing HIIT program in healthy male non-athletes?
Summary
Healthy young men did 8 weeks of supervised rowing HIIT while taking ashwagandha or placebo. Training improved rowing test performance and absolute aerobic capacity markers, but ashwagandha did not provide extra benefits for aerobic capacity or resting blood measures; muscle oxygenation findings were mixed and favored placebo on some indices.
Methodology
- Healthy male physical education students/non-athletes
- 33 participants.
- Rowing ergometer.
- Work intervals: 1.5 minutes.
- Recovery: 1.5 minutes at 70 W.
- Intensity: 75-95% maximal aerobic power by study week.
- About 15-21 minutes of interval/recovery work.
- 3 sessions/week.
- 8 weeks.
- Randomized double-blind placebo-controlled supplementation trial with supervised rowing HIIT in both groups
- Aerobic capacity, Muscle oxygenation, and Hematology were tracked.
Outcomes
Aerobic capacity
Both groups improved test time, maximal aerobic power, anaerobic threshold power, and absolute VO2max, with no added ashwagandha effect.
Significant time effects for test time, MAP, PAT4, and absolute VO2max; no significant group or interaction effects.
Relative VO2max
Relative VO2max did not significantly improve.
Reported p=0.15.
Muscle oxygenation
Some SmO2 indices improved in placebo but not ashwagandha, with no clear supplement advantage.
Time-by-group effects were reported for SmO2Min and delta SmO2; post hoc improvements occurred in placebo.
Hematology
Resting hematological parameters did not show meaningful supplement or training changes.
No significant group or interaction effects were reported.
Insights
- The training program, not the ashwagandha supplement, accounts for the observed performance-related improvements.
- Relative-power rowing HIIT is reproducible but requires equipment and testing.
- Muscle oxygenation findings should not be converted into consumer claims without replication.
Limitations
- Small sample of healthy young men.
- No non-exercise control group.
- Technical exclusions for muscle oxygenation.
- Relative VO2max did not improve significantly.
- Adverse-event and session adherence details were not reported.
Safety
- Three participants dropped out for personal reasons.
- Five participants were excluded from analysis because of technical problems measuring muscle oxygenation.
- No adverse-event outcomes were reported in the extracted article.