Impact of high-intensity exercise on energy expenditure, lipid oxidation and body fatness

Abstract

OBJECTIVE: Two studies were conducted to assess the potential of an increase in exercise intensity to alter energy and lipid metabolism and body fatness under conditions mimicking real life. METHODS: Study 1 was based on the comparison of adiposity markers obtained in 352 male healthy adults who participated in the Que Âbec Family Study who either regularly participated in high-intensity physical activities or did not. Study 2 was designed to determine the effects of high-intensity exercise on post-exercise post-prandial energy and lipid metabolism as well as the contribution of b-adrenergic stimulation to such differences under a real-life setting. RESULTS: Results from Study 1 showed that men who regularly take part in intense physical activities display lower fat percentage and subcutaneous adiposity than men who never perform such activities, and this was true even if the latter group reported a lower energy intake (917 kJaday, P`0.05). In Study 2, the high-intensity exercise stimulus produced a greater postexercise post-prandial oxygen consumption as well as fat oxidation than the resting session, an effect which disappeared with the addition of propranolol. In addition, the increase in post-prandial oxygen consumption observed after the high-intensity exercise session was also signi®cantly greater than that promoted by the low-intensity exercise session. CONCLUSION: These results suggest that high-intensity exercise favors a lesser body fat deposition which might be related to an increase in post-exercise energy metabolism that is mediated by b-adrenergic stimulation.

Long-period accelerometer monitoring shows the role of physical activity in overweight and obesity

“…These results also support the notion that individuals who engage in vigorous PA are leaner than individuals who never take part in such activities. 8 On the other hand, the current study shows that energy expenditure due to PA and TEE in overweight and obese are, respectively, similar and higher than normal weight. The obese individuals are often less active, but since they carry a heavier load requiring more energy, their TEE may not be lower.…”

“…6 Moreover, a participation in vigorous PA is related with a lower adiposity. 7,8 Therefore, the amount as well as the intensity of PA might be important potential determinants of overweight and obesity in Japanese population.…”

“…Although questionnaires have a disadvantage that subjects can easily overestimate or underestimate PA, 13 most population studies [4][5][6] have used a questionnaire to assess a daily PA because of its convenience. In some epidemiological studies, PA records were also used to estimate the amount and intensity of PA. 7,8 However, these procedures are very demanding for subjects. In contrast, the accelerometer is small, light, and easy to use.…”

Does physical activity equally predict gain in fat mass among obese and nonobese young adults?

“…[15][16][17][18][19] The impact of exercise intensity on change in body composition is equivocal. [20][21][22][23] Our results suggest that change in overall activity, but not change in any of the subcomponents of activity, is inversely associated with change in FM. This would then suggest that an increase in overall PA, regardless of the exercise intensity, might be an effective strategy to prevent FM gain.…”

“…[15][16][17][18][19] One recent study has suggested a prospective association between PA and change in FM but this association was modified by age. 20 Furthermore, the potential impact of exercise intensity on change in BW and FM remains elusive, [21][22][23][24] and it is not known which if any of the subcomponents of free-living PA contributes more to change in BW and FM.…”