Consistency in compensatory eating responses following acute exercise in inactive, overweight and obese women

Abstract

It is often assumed that some individuals reliably increase energy intake (EI) post-exercise ('compensators') and some do not ('non-compensators'), leading researchers to examine the characteristics that distinguish these two groups. However, it is unclear whether EI post-exercise is stable over time. The present study examined whether compensatory eating responses to a single exercise bout are consistent within individuals across three pairs of trials. Physically inactive, overweight/obese women (n 28, BMI 30·3 (SD 2·9) kg/m²) participated in three pairs of testing sessions, with each pair consisting of an exercise (30 min of moderate-intensity walking) and resting testing day. EI was measured using a buffet meal 1 h post-exercise/rest. For each pair, the difference in EI (EIdiff = EIex - EIrest) was calculated, where EIex is the EI of the exercise session and EIrest is the EI of the resting session, and women were classified as a 'compensator' (EIex > EIrest) or 'non-compensator' (EIex ≤ EIrest). The average EI on exercise days (3328·0 (SD 1686·2) kJ) was similar to those on resting days (3269·4 (SD 1582·4) kJ) (P= 0·67). Although EI was reliable within individuals across the three resting days (intraclass correlation coefficient (ICC) 0·75, 95 % CI 0·60, 0·87; P< 0·001) and three exercise days (ICC 0·83, 95 % CI 0·70, 0·91; P< 0·001), the ICC for EIdiff across the three pairs of trials was low (ICC 0·20, 95 % CI -0·02, 0·45; P= 0·04), suggesting that compensatory eating post-exercise is not a stable construct. Moreover, the classification of 'compensators'/'non-compensators' was not reliable (κ = -0·048; P= 0·66). The results were unaltered when 'relative' EI was used, which considers the energy expenditure of the exercise/resting sessions. Acute compensatory EI following an exercise bout is not reliable in overweight women. Seeking to understand what distinguishes 'compensators' from 'non-compensators' based on a single eating episode post-exercise is not justified.

Trial registration: ClinicalTrials.gov NCT01330329.

Keywords: Obesity.

Conflict of interest statement

Conflict of Interest

None

Figures

Figure 1

Study Overview * participants were randomized to a specific order of testing visits using a randomized, counter-balanced design

Figure 2

Summary of Experimental Testing Visits Comp Tasks = completion of computer tasks and questionnaires

Figure 3

Individual energy intake difference between exercise and resting sessions for each pair of trials Energy intake difference calculated as EIex minus EIrest. Positive values indicate “compensation” and negative values indicate “non-compensation.” The dashed line reflects the net energy expenditure (EEex – EErest) of the exercise session; thus participants above the dashed line would be classified as “compensators” using the relative energy intake criteria for compensation.

Figure 3

Individual energy intake difference between exercise and resting sessions for each pair of trials Energy intake difference calculated as EIex minus EIrest. Positive values indicate “compensation” and negative values indicate “non-compensation.” The dashed line reflects the net energy expenditure (EEex – EErest) of the exercise session; thus participants above the dashed line would be classified as “compensators” using the relative energy intake criteria for compensation.

Figure 4

The difference in energy intake between exercise and resting sessions for each individual for each of the 3 pairs of trials Energy intake difference calculated as EIex minus EIrest; thus a positive value indicates “compensation” (i.e., an individual ate more after exercise compared to rest).