Metabolic and Behavioral Compensatory Responses to Exercise Interventions: Barriers to Weight Loss

Abstract

An activity-induced increase in energy expenditure theoretically disturbs energy balance (EB) by creating an acute energy deficit. Compensatory responses could influence the weight loss associated with the energy deficit. Individual variability in compensation for perturbations in EB could partly explain why some individuals fail to lose weight with exercise. It is accepted that the regulatory system will readily defend impositions that promote a negative EB. Therefore, a criticism of exercise interventions is that they will be ineffective and futile methods of weight control because the acute energy deficit is counteracted. Compensation for exercise-induced energy deficits can be categorized into behavioral or metabolic responses and automatic or volitional. An automatic compensatory response is a biological inevitability and considered to be obligatory. An automatic compensatory response is typically a metabolic consequence (e.g., reduced resting metabolic rate) of a negative EB. In contrast, a volitional compensatory response tends to be deliberate and behavioral, which the individual intentionally performs (e.g., increased snack intake). The purpose of this review is to highlight the various metabolic and behavioral compensatory responses that could reduce the effectiveness of exercise and explain why some individuals experience a lower than expected weight loss. We propose that the extent and degree of compensation will vary between individuals. That is, some individuals will be predisposed to compensatory responses that render them resistant to the weight loss benefits theoretically associated with an exercise-induced increase in energy expenditure. Therefore, given the inter-individual variability in behavioral and metabolic compensatory responses, exercise prescriptions might be more effective if tailored to suit individuals.

Appetite, gut hormone and energy intake responses to low volume sprint interval and traditional endurance exercise

“…However, such changes in ghrelin do not appear to reduce appetite or aid weight loss in the obese (Cummings et al 2002). It must be noted that ghrelin is only one component of the appetiteregulating neuroendocrine system and that appetite is likely to reflect many hormonal and psychological factors (King et al 2007;Murphy and Bloom 2006). Nevertheless, the present study adds to the debate surrounding the importance of physiological decreases in acylated ghrelin as a determinant of appetite.…”

Does metabolic compensation explain the majority of less-than-expected weight loss in obese adults during a short-term severe diet and exercise intervention?

“…38 Further, we, and others, have shown reductions in non-exercise activity thermogenesis in overweight and obese individuals in response to exercise training and/or caloric restriction interventions. [39][40][41] Given that accurate measurement of daily physical activity and activity energy expenditure can be challenging in studies of freeliving humans, it is useful to consider evidence from highlycontrolled animal studies. High inter-animal variability in weight loss was reported in a recent study of MF1 mice that were restricted to 70% of their individual baseline food intake for 28 days.…”

Influence of prolonged treadmill running on appetite, energy intake and circulating concentrations of acylated ghrelin

“…Exercise is effective at preventing weight gain and maintaining a reduced body weight following weight loss however in the absence of a calorie restricted diet the ability of exercise to induce weight loss is less certain (Catenacci & Wyatt, 2007;Donnelly et al, 2009;Seagle et al, 2009). A possible explanation for this is that exercise may elicit compensatory increases in appetite and energy intake, responses that would negate the ability to induce a sustained energy deficit (King et al, 2007).…”