Behavioral and physiological regulation of body fatness: a cross-sectional study in elderly men

Abstract

Objective: To identify the characteristics of physical activity that are the most correlated to total and truncal fatness and to physiological parameters involved in fat oxidation in elderly men. Design: Cross-sectional study. Subjects: A total of 25 healthy elderly men selected with a wide range of physical activity behavior (65.973.4 years). Measurements: Total and truncal fat masses (by dual-energy X-ray absorptiometry), time spent and energy expended (EE day ) at specific activity intensities (o40, 40-60, 460% VO 2max ) during 1 week in free living conditions (using heart rate recording and individual calibrated equations), sport-exercising volume (V sport , using Baecke questionnaire), maximal oxygen uptake (VO 2max ), muscle fat oxidative capacity (OX FA , using muscle biopsy), lipid oxidation and respiratory exchange ratio during exercise at 50% VO 2max (using indirect calorimetry). Results: V sport was the main determinant of total and truncal fatness, VO 2max and OX FA (r ¼ À0.69, Po0.0001; r ¼ À0.80, Po0.0001; r ¼ 0.70, Po0.0001; r ¼ 0.66, Po0.001, respectively). Among physical activity parameters measured over a week, total EE day was the main determinant of total fat mass. Furthermore, EE day at % VO 2max 460 was closely correlated to truncal fat mass, VO 2max and OX FA (r ¼ À0.58, P40.01; r ¼ 0.55, Po0.01; r ¼ 0.49, Po0.05, respectively). Finally, VO 2max and OX FA were positively correlated to absolute fat oxidation and to the contribution of fat to energy production during moderate exercise. Conclusion: Sport-exercising volume is the main factor regulating total and truncal fat masses and physiological parameters involved in fat oxidation. With regard to the characteristics of physical activity, overall energy expended during the alert period plays a major role in the regulation of total body fatness. In addition, vigorous exercises may be beneficial for the regulation of abdominal fat depot partly through the stimulation of muscle fat oxidation during the effort.

Rapid down‐regulation of mitochondrial fat metabolism in human muscle after training cessation is dissociated from changes in insulin sensitivity

“…The subjects stopped sport exercise 2 days before initial metabolic measurements that included basal indirect calorimetric measurement, muscle biopsy, 3‐h euglycemic–hyperinsulinemic clamp, and body composition determination. From two days before and throughout the metabolic measurements, the volunteers were placed on a controlled diet (35%, 50% and 15% of energy in the form of lipids, carbohydrates and proteins, respectively) [12]. Heart rate was re‐recorded over 7 days in free‐living conditions at the end of the training cessation period.…”

“…The tests were all performed on the same cycloergometer (Ergomeca, Monark, Sweden) under cardiovascular supervision by a cardiologist, as described in [12].…”

“…HR was recorded minute‐by‐minute using telemetry (Polar protrainer™, Polar Electro Oy, Finland) during seven consecutive days. The time spent per day at specific activity intensities (<40%, 40–60% and >60% of VO 2max ) was calculated using the individual relationship between HR and %VO 2max established during the maximal aerobic power test [12].…”

Yearlong physical activity and sarcopenia in older adults: the Nakanojo Study

“…A number of cross-sectional (Aubertin-Leheudre et al 2006;Baumgartner et al 1998;Melton et al 2000;Rimbert et al 2006;Starling et al 1999;Szulc et al 2004) and longitudinal studies (Hughes et al 2001;Rantanen et al 1997) have shown relationships between low levels of habitual physical activity and the presence or the development of sarcopenia. However, one limitation in most of these studies (Baumgartner et al 1998;Hughes et al 2001;Melton et al 2000;Rantanen et al 1997;Rimbert et al 2006;Szulc et al 2004) was that physical activity patterns were assessed by questionnaires; commonly, inquiry was made Communicated by Roberto Bottinelli.…”

“…However, one limitation in most of these studies (Baumgartner et al 1998;Hughes et al 2001;Melton et al 2000;Rantanen et al 1997;Rimbert et al 2006;Szulc et al 2004) was that physical activity patterns were assessed by questionnaires; commonly, inquiry was made Communicated by Roberto Bottinelli.…”