High Intensity Interval Training Does Not Have Compensatory Effects on Physical Activity Levels in Older Adults

Abstract

Background: Exercise has beneficial effects on older adults, but controversy surrounds the purported "compensatory effects" that training may have on total daily physical activity and energy expenditure in the elderly. We wanted to determine whether 8 weeks of high-intensity interval training (HIIT) induced such effects on physical activity and energy expenditure in healthy, active older adult men.

Methods: Twenty-four healthy elderly male volunteers were randomized to two groups. The experimental group performed HIIT (7 × 2 min cycling repetitions, 3 d/w); the control group performed continuous moderate-intensity training (20-30 min cycling, 3 d/w). Physical activity and energy expenditure were measured with a multisensor activity monitor SenseWear Armband Mini.

Results: During HIIT, significant changes were observed in moderate and vigorous physical activity, average daily metabolic equivalents (METs), physical activity level, and activity energy expenditure (p < 0.05) but not in total energy expenditure. Sleep and sedentary time, and levels of light physical activity remained constant during the training period.

Conclusions: The findings suggest that HIIT induced no compensatory effect: HIIT does not adversely affect lifestyle, as it does not reduce daily energy expenditure and/or increase sedentary time.

Keywords: ageing; elderly; energy expenditure; high-intensity interval training; lifestyle; physical activity.

Figure 1

Assessment timeline; PA (Physical activity) evaluation; T1: Evaluation before the training; T2: Evaluation during training T3: Evaluation after training.

Figure 2

Mean of components of daily physical activity (Sleep, sleep time; SED, sedentary activity, intensity < 1.5 METs; LPA, light intensity physical activity, 1.5–3 METs; MPA, moderate intensity physical activity, 3–6 METs; VPA intensity physical activity > 6 METs) before the training period (T1), one week during training period (T2), and one week after two months of the end of the training (T3). Repeated measure Anova (* Significantly different, p < 0.05). (A) EXP group; (B) CTRL group.

Figure 3

Mean of components of total energy expenditure (TEE) before the training period (T1), one week during training (T2), and one week after two months of the end of the training (T3). TEE: total energy expenditure; REE: resting energy expenditure; AEE: activity energy expenditure; DIT: Diet induced thermogenesis. Repeated measure Anova (*Significantly different compared to T2, p < 0.05). (A) EXP group; (B) CTRL group.