Purpose: There is conflicting evidence whether a single bout of resistance exercise performed the day before a test meal can lower postprandial triacylglycerol (TAG) concentrations. The present study examined the effect of a single session of resistance exercise, performed the same day as a test meal, on postprandial TAG concentrations in resistance-trained males.
Methods: Ten healthy males aged 25 (SD 2.6) yr performed two trials at least 1 wk apart in a counterbalanced, randomized design. In each trial, participants consumed a test meal (0.89 g of fat, 1.23 g of carbohydrate, 0.4 g of protein, 60 kJ·kg−1 body mass). Before one meal, participants performed a 90-min bout of resistance exercise. Before the other meal, participants were inactive (control trial). Resistance exercise was performed using free weights and included three sets of 12 repetitions of each of 10 exercises. Sets were performed at 80% of 12-repetition maximum with a 3-min work and rest interval. Venous blood samples were obtained in the fasted state and for 5 h postprandially.
Results: Total area under the plasma TAG concentration versus time curve was higher (Student‘s t-test P = 0.008) on the exercise than control trial (mean ± SE: 11.76 ± 1.64 vs 7.94 ± 1.08 mmol·L−1·5 h−1, respectively). Total area under the plasma myoglobin concentration versus time curve was higher (Student‘s t-test P = 0.010) on the exercise than control trial (16.68 ± 3.34 vs 6.80 ± 0.64 nmol·L−1·5 h−1; respectively).
Conclusion: A single bout of resistance exercise can cause a transient elevation in postprandial TAG concentrations. The elevations in plasma myoglobin suggest postexercise muscle damage. Further investigation is needed to see if these findings are linked.
School of Sport and Exercise Sciences, Loughborough University, Loughborough, Leicestershire, UNITED KINGDOM
Submitted for publication April 2005.
Accepted for publication September 2005.
Address for correspondence: David Stensel, School of Sport and Exercise Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK; E-mail: firstname.lastname@example.org.