Interval training causes the same exercise enjoyment as moderate-intensity training to improve cardiorespiratory fitness and body composition in young Chinese women with elevated BMI

Abstract

ABSTRACT This study examined the effects of 12 weeks of sprint interval training (SIT), high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cardiorespiratory fitness (peak oxygen uptake, VO2peak), body composition and physical activity enjoyment in overweight young women. Sixty-six participants (age 21.2 ± 1.4 years, body mass index (BMI) 26.0 ± 3.0 kg·m−2, body fat percentage 39.0 ± 2.8%) were randomly assigned to non-exercise control (CON), thrice-weekly SIT (80 × 6 s “all-out” cycling interspersed with 9 s rest), and HIIT (4 min cycling at 90% VO2peak followed with 3 min recovery for ~ 60 min) or MICT (~ 65 min continuous cycling at 60% VO2peak) with equivalent mechanical work (200/300 KJ). Compared to the CON group, all three training groups had significant and similar improvements in VO2peak (~ +20%, d = 2.5–3.4), fat mass (~ −10%, d = 1.3–2.1) and body fat percentage (~ −5%, d = 1.0–1.1) after a 12-week intervention. Similar high levels of enjoyment were observed among groups for most (~70%) of the training sessions. The findings suggest that the three training regimes are equally enjoyable and could result in similar improvements in cardiorespiratory fitness and body composition in overweight/obese young women, but SIT is a more time-efficient strategy.