Effects of Low-Volume High-Intensity Interval Training on Physical Performance in Older Adults With Possible...

To compare the effects of low-volume high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) on physical performance, muscle strength, and exercise enjoyment in older adults with possible sarcopenia.

A 2-arm, assessor-blind randomized controlled trial.

Community-based.

Thirty older adults (N=30) with possible sarcopenia (mean ± SD age, 66.0±3.7y, 67% women).

Participants were randomized to either a 15-minute HIIT protocol (5×1-min cycling at 77%-90% maximum heart rate or 15-17 ratings of perceived exertion interspersed with 1-min recovery; n=15) or 25-minute MICT protocol (cycling at 65%-76% maximum heart rate or 12-14 ratings of perceived exertion; n=15), performed for 3 days per week for 7 weeks.

The primary outcome was the 5 times sit to stand test. Secondary outcomes included comfortable walking speed, handgrip strength, and functional reach test. Exploratory outcomes were exercise enjoyment assessed using the Physical Activity Enjoyment Scale and the Exercise Enjoyment Scale.

The HIIT group showed greater improvements in 5 times sit to stand test compared with the MICT group postintervention (Δ-0.57s [95% CI, -1.10 to -0.04]; P=.04; η²=0.15), at 1-month (Δ-0.58s [95% CI, -1.13 to -0.04]; P=.04; η²=0.15), and 3-month follow-ups (Δ-0.58s [95% CI, -1.13 to -0.02]; P=.04; η²=0.14). Both groups demonstrated significant improvements over time in 5 times sit to stand test time (P<.001; η²=0.77), comfortable walking speed (P<.001; η²=0.79), handgrip strength (P<.001; η²=0.88), and functional reach test (P<.001; η²=0.78). Participants in the HIIT group reported significantly higher scores on the Physical Activity Enjoyment Scale and the Exercise Enjoyment Scale compared with those in the MICT group.

HIIT provides superior and sustained improvements in physical performance, as well as greater exercise enjoyment, over MICT in older adults with possible sarcopenia.