How much exercise should be promoted to raise total daily energy expenditure and improve health?

Abstract

Despite longstanding recognition of the benefits of a physically active lifestyle, there remains ambiguity regarding exactly how much exercise should be promoted to raise total energy expenditure (TEE) and improve health. This review provides a brief summary of the dose-response relationship between physical activity and relative risk of morbidity and mortality; mechanisms through which exercise drives an increase in TEE; the highest reported levels of TEE measured via doubly labelled water; and the potential impact of non-compliance and confounders in moderating the contribution of exercise to increase TEE. Cohort studies provide a compelling argument that 'more is better' regarding the exercise dose for increasing TEE, that increasing TEE is protective for health, and that this is mediated through increased cardiorespiratory fitness. However, growing evidence shows that ever increasing volumes of weekly physical activity may reverse the cost-benefit seen with more modest doses. Animal and human studies show that the elevation in TEE associated with increasing exercise volume is commonly less than expected, due to physiological confounders. Further, there is considerable evidence of behavioural non-compliance to planned exercise in all but the most highly motivated athletes. Therefore, inbuilt defence mechanisms may safeguard against TEE being elevated to maximum levels.

Sedentary behavior compensation to 1‐year exercise RCT in patients with type 2 diabetes

“…Women from the HIIT group significantly reduced their sitting time corroborating previous findings in healthy individuals in whom total sedentary time was objectively measured . In contrast, others have suggested a compensatory reduction in non‐exercise PA in response to aerobic exercise, and that people engaging in more MVPA will increase sedentary behaviors during the rest of the day to counteract the energy expenditure increases . There is rationale to justify both potential contradictory responses to an exercise intervention .…”

“…35 There is rationale to justify both potential contradictory responses to an exercise intervention. 35 For example, people engaging in more MVPA during an exercise intervention may change their mindset and therefore alter their behavior in a general manner in order to become healthier, by also increasing their PA in the time outside the training sessions. Others may compensate their increases in MVPA, by reducing PA and increasing sedentary behaviors in the time between exercise sessions so that they can maintain a constant daily energy expenditure, possibly defined by an unconscious set-point.…”

Targeting lifestyle energy expenditure in the management of obesity and health: from biology to built environment

“…As to the issue raised by Byrne and Hills concerning physiological confounders in moderating the contribution of exercise to increase TEE, this is further elaborated by Doucet et al . in their analysis of the compensation to energy deficits induced by exercise or diet.…”

“…Amid the unequivocal recognition of other benefits of a physically active lifestyle for body and mind and the numerous research‐based proposals for exercise‐type training, exercise recommendations and exercise prescriptions, a challenging question is: How much exercise should be promoted to raise daily EE and improve health? Byrne and Hills take up the challenge and critically analyse this issue from several perspectives, namely, (i) the importance of raising daily total EE (TEE) to improve health by examining the dose–response relationship between physical activity and relative risk of morbidity and mortality, (ii) the multiple mechanisms through which exercise can drive an increase in TEE (both directly through changes in various compartments of TEE and indirectly through training adaptations), (iii) the key question of whether a theoretical ‘ceiling’ for further increasing TEE may exist and (iv) the potential impact of behavioural non‐compliance and physiological confounders in moderating the contribution of exercise to increase TEE.…”

Obesidade associada às reduzidas massa magra e massa óssea: uma emergente e complexa relação envolvendo alterações bioquímicas, metabólicas e funcionais

“…Por meio desta técnica, administra-se ao indivíduo uma dose de água marcada com os isótopos estáveis deutério ( 2 H) e oxigênio-18 ( 18 O) e a diferença de eliminação na urina entre ambos reflete a produção e eliminação de dióxido de carbono (CO2) via expiração. O volume de CO2 é então empregado em equações para determinação do GET162 , e o NAF é derivado a partir da razão entre o GET e a TMR151 .Uma das possíveis e mais plausíveis explicações do efeito positivo do NAF sobre o estado geral de saúde compreende, além de seu impacto sobre o GET, sua capacidade de predizer a aptidão cardiorrespiratória (ACR)163 . 1.4.3.2.…”