Effect of exercise training interventions on energy intake and appetite control in adults with overweight or obesity: A systematic review and meta‐analysis

Summary This systematic review examined the impact of exercise training interventions on energy intake (EI) and appetite control in adults with overweight/obesity (≥18 years including older adults). Articles were searched up to October 2019. Changes in EI, fasting appetite sensations, and eating behavior traits were examined with random effects meta‐analysis, and other outcomes were synthesized qualitatively. Forty‐eight articles were included (median [range] BMI = 30.6 [27.0–38.4] kg/m2). Study quality was rated as poor, fair, and good in 39, seven, and two studies, respectively. Daily EI was assessed objectively (N = 4), by self‐report (N = 22), with a combination of the two (N = 4) or calculated from doubly labeled water (N = 1). In studies rated fair/good, no significant changes in pre‐post daily EI were found and a small but negligible (SMD < 0.20) postintervention difference when compared with no‐exercise control groups was observed (five study arms; MD = 102 [1, 203] kcal). There were negligible‐to‐small pre‐post increases in fasting hunger and dietary restraint, decrease in disinhibition, and some positive changes in satiety and food reward/preferences. Within the limitations imposed by the quality of the included studies, exercise training (median duration of 12 weeks) leads to a small increase in fasting hunger and a small change in average EI only in studies rated fair/good. Exercise training may also reduce the susceptibility to overconsumption (PROSPERO: CRD42019157823).

"[…] moderate-to-high intensity morning exercise could lead to significant changes in calorie intake and body composition over weeks, while exercising in the evening did not make such differences" Agree that results demonstrate potential benefits of morning exercise on body weight and appetite control, but conclusions based on selfreported measures of energy intake.
"We found that energy intakes did not increase in response to aerobic or resistance exercise' in fact, energy intakes decreased slightly between the beginning and the end of training. These results counter the claim that sedentary individuals who initiate a long-term exercise program increase their energy intakes in a compensatory fashion." Appropriate conclusions based on available data, but important to take into account that conclusions are based on selfreported measures of energy intake.
-No exercise effects on food intake at buffet meal.
-Prospective food consumption before lunch increased in the controls relative to 20 KKW (7 (3); p=0.03, main effect of group).
"We additionally showed that appetitive measures, anthropometry, and body composition were not appreciably affected by the interaction between race and exercise." Appropriate conclusions based on available data.
-Reduction in carbohydrate intake (g) from baseline to month 3, 9 and 15 (all p<0.05). - No change in overall diet quality across the intervention.
-From baseline to 3 months, HEI-2010 scores for whole fruit, whole grains and refined grains decreased (p<0.01). Whole fruit and refined grain scores returned to baseline during maintenance phase.
-Total vegetable and greens and beans score increased (p<0.002) during maintenance phase (month 3 to 9), but returned to baseline during no-contact phase. -No change in fasting or 120min hunger.
"[…] exercise tended to reduce total energy and protein intake independent of intensity, suggesting that training prevented compensatory weight gain.
[…] Further research is required to better understand how these outcomes of appetite are affected by long-term exercise […]" Appropriate conclusions based on available data and small effects, but important to take into account that conclusions are based on selfreported energy intake and a 2-wk intervention. -Energy intake decreased more in points-based (-445 kcal) and control (-233 kcal) groups than structured exercise group (-52 kcal; interaction p=0.054).
"[Modest but meaningful reductions in body weight and body fat with a pointsbased approach to physical activity] is likely a result of modest reductions in sedentary time, increases in light activity and a spill-over effect of altered eating behaviour and reduced energy intake." Appropriate conclusions based on available data, but important to take into account that conclusions are based on selfreported energy intake.
-Eating behaviour score improved post-intervention (from "[Individuals who lose weight with physical activity] may also self-select to change their eating behaviors, which in combination with physical activity, resulted in the Weight loss group × time interaction (p<0.001) for change in eating behavior score, with weight losers (10.0 (9.9)) increasing more than weight maintainers (2.8 (6.8)) and gainers (4.9 (10.4)). significant decrease in weight." (energy intake is self-reported).

maintainers & weight gainers
Kirkwood et al. (2007) - In physical activity group, energy intake only decreased at wk 6 by 213 kcal/d (p<0.05) (energy intake also decreased in control group relative to baseline, by 357 kcal at wk 6 and 371 kcal wk 12, p<0.05).
-Greater change in protein intake in diet and diet+activity "This highlights the need for dietary advice to accompany advice on increasing activity to achieve weight loss." Conclusions weak as based on unsupervised exercise intervention and self-reported energy intake. Carbohydrate intake (g) decreased by 23 g in exercise group and increased by 19 g in control group (interaction p=0.013) -Difference in the change in number of bread/cereal exchanges across groups (p<0.006), exercise group decreased by 1.6 exchange whereas control group increased by 0.9 exchange.
energy expenditure]. Thus exercise training by the obese can help prevent weight gain and should, in the long term, lead to a negative energy balance and promote weight loss." and small effects, but important to take into account that conclusions are based on selfreported energy intake.
Quist et al. - At 3 months, test meal energy intake was lower in vigorous relative to control (-280 kcal, p<0.01). At 6 months, test meal energy intake was lower in vigorous relative to moderate (-158 kcal, p=0.03). No differences found for cumulative daily energy intake.
-At 6 months, fasting hunger was higher in bike relative to vigorous (+13 mm, p=0.03) -At 3 months, postprandial prospective food consumption was lower in moderate (-19%, p=0.02) and vigorous (-30%, p<0.001) relative to control, and in vigorous relative to bike (p<0.01). Hunger was lower in moderate (p=0.04) and vigorous (p<0.01) compared to bike. At 6 "In summary, 6 mo of active commuting and leisure-time exercise of different intensities did not increase markers of appetite in women and men with overweight and obesity. […] Furthermore, our findings suggest that exercise needs to be of vigorous intensity to affect appetite in individuals with overweight and obesity." Appropriate conclusions based on available data. Relative to diet groups, exercise only and control groups did not change energy intake over the intervention.

Outcomes not discussed.
Exercise alone appeared to have minimal impact on self-reported energy intake.
-Susceptibility to hunger increased in both exercise groups from wk -4 to wk 12 (data not shown, p=0.004).
-Wanting for fat decreased across both exercise groups from wk 1 to wk 12-14 (data not shown; p=0.03).
-Increase in liking for savoury foods pre-to post-acute exercise at wk 1 but decrease at wk 12-14 (data not shown; interaction p=0.002).
[ -In total sample, no significant change in absolute energy intake from baseline to postintervention but energy intake relative to body weight increased in the 600 kcal group (32.3 (6.3) kcal/kg/day to 35.4 (8.2) kcal/kg/day and was unchanged in the 400 kcal and control groups from baseline to 10 months (group-time interaction p<0.01). - In women, absolute energy intake was greater in the 600 "In summary, we found no significant change in energy or macronutrient intake in response to a 10-month supervised exercise program in overweight and obese young adults.

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Significant main effect of training on high-energy density meal size (7.04 (2.49) to 6.80 (3.26) MJ, p<0.005) but not low-energy density meal size (4.60 (1.85) to 4.28 (1.76) MJ). - No main effect of training on daily energy intake under each dietary condition.

Outcomes not discussed.
Exercise appeared to have reduced intake at a highenergy-density test meal, but this did not impact total daily energy intake. No changes in eating behaviour traits or post-prandial appetite ratings. - Reduced neuronal responses to visual food cues after intervention in bilateral parietal cortices, left insula and visual cortex (p<0.01). - No change in the acute exercise response with exercise training.
"Measures of eating-related behaviors and appetite, however, were not affected by the exercise intervention even despite modest weight/fat loss, suggesting that exercise may attenuate the changes in ingestive behavior expected with negative energy balance." Appropriate conclusions based on available data, but important to take into account that conclusions are based on selfreported energy intake. Outcomes not discussed.
Exercise appeared to have minimal impact on selfreported energy intake.

NR NR
Garnier et al.
-No change in total energy intake post-intervention. -% energy from carbohydrate decreased (-1.0 (6.2) %) and % energy from protein "The main findings of our study indicate that although our walking program changed food consumption patterns, it did not have much impact on energy Appropriate conclusions based on available data, but important to take into account that conclusions  Women with the greatest reduction in fat mass had the highest decrease in fatty foods consumption (-0.20 (0.19)  Non-responders and responders had significantly greater fasting hunger (+24 and +38% change, respectively, p<0.001) but also had a greater satiety quotient post-training -Only non-responders increased daily motivation to eat post-training (greater hunger, desire to eat and lower fullness, +43, +6 and -10%, respectively; p<0.005).
"[…] the effect of exercise on appetite regulation involves at least 2 processes: an increase in the overall (orexigenic) drive to eat and a concomitant increase in the satiating efficiency of a fixed meal." Appropriate conclusions based on available data.
"[…] our data confirm that there is a large degree of interindividual variability in body fat loss in response to an exercise training intervention and indicated that, in overweight women, compensatory reductions in [energy expenditure] of physical activity outside exercise intervention can contribute to the failure of exercise to successfully induce fat loss." Conclusions based on self-reported energy intake (which did not differ between groups), and it is hypothesized that only compensatory adaptations in energy expenditure lead to differences in body fat loss in response to exercise. -There was an increase in fasted hunger (4.1 (1.6) to 6.5 (2.5) cm; p<0.01), desire to eat (4.8 (1.5) to 6.4 (2.3) cm; p<0.05) and prospective food consumption (6.0 (1.6) to 7.1 (2.0) cm; p<0.05), and a Week by time interaction for postprandial fullness (p<0.01; post hoc comparisons not shown).
increased orexigenic drive by improving the satiety response to a meal and the sensitivity of the appetite control system."

Martins et al. (2013)
- No change in test meal energy intake.
-Exercise-preload interaction (p=0.011) showing that cumulative energy intake after high-energy preload was higher than after the low-energy preload at baseline (2118 (775) vs 1803 (421) kcal, p=0.001), whereas post-training, cumulative energy intake after the high-energy preload was lower than after the low-energy preload (1799 (649)  No changes in energy intake over the 57 days.
"The combination of moderate exercise with energy intake at the level self-selected in this study produced a negative energy balance. Therefore, exercise, if combined with a palatable but not gourmet diet, can be useful treatment for weight reduction." Appropriate conclusions based on available data, but based on very small sample size.
-Tendency for increase with MIIT (+6 (20) mm) and decrease with HIIT (-13 (16) mm) in explicit liking for high-fat non-sweet foods after acute exercise post-training (interaction p=0.09). - No effects of training on food intake or energy intake.
"The tendencies of eating behaviour including medium term-Ex hunger and desire to eat, medium term-Ex explicit liking for energydense food, medium-term constant-load exerciseinduced food and fat intake collectively suggested that HIIT is a better strategy than MIIT to minimize the compensation of eating Tendency for fat intake (g) to increase after MIIT (+14 g) and decrease after HIIT (-7 g; interaction p=0.07).
behaviour during interval training among males."