Gholipour M, Kordi Mr, Taghikhani M, Ravasi Aa, Gaeini Aa, Tabrizi A,
Volume 69, Issue 2 (5-2011)
Abstract
Background: Body weight is regulated by both food intake and energy expenditure. Ghrelin, a hormone produced by the stomach and pancreas, enhances appetite. This study was undertaken to determine the effects of intermittent treadmill running on acylated ghrelin and appetite in individuals with obesity.
Methods: Nine inactive male students, with a mean age of 20.56±0.48 yrs, a body mass index of 32.68±0.84 kg/m2 and a maximum oxygen uptake of 34.21±1.48 ml/kg/min, participated in the study in two trials (control and exercise) in a counterbalanced, randomized design. The protocol included intermittent running with a constant intensity at 65% of VO2 max on a treadmill. Blood samples were collected before, during, and 2h after cessation of the exercise.
Results: Acylated ghrelin concentrations and hunger ratings decreased significantly in the second phase and remained lower than baseline (P=0.006 and P=0.002, respectively) at the end of the exercise. The total area under the curve values and hunger ratings (all P<0.0005) were significantly lower in the exercise trial compared with the control state. Similarly, growth hormone rose significantly at the second phase and remained higher than baseline (P=0.033) at the end of the exercise trial.
Conclusion: These findings indicate that acylated ghrelin and appetite are reduced by running at 65% of VO2 max and remain lower than baseline even two hours afterwards in individuals with obesity. Growth hormone seems to be more responsible for this
suppression. Further studies are required to investigate whether this protocol could
elicit the same effects in short-term training programs.
Majid Gholipour , Arezoo Tabrizi ,
Volume 71, Issue 5 (8-2013)
Abstract
Background: The prevalence of obesity has risen enormously over the past few decad-es. Both food intake (Appetite) and energy expenditure can influence body weight. Acylated ghrelin enhances appetite, and its plasma level is suppressed by growth horm-one. The present study, examines the effects of an intermittent exercise with progress-ive intensities on acylated ghrelin, appetite, and growth hormone in inactive male students with two levels of obesity.
Methods: Eleven inactive males were allocated into two groups on the basis of their body mass index (BMI). Six subjects in group one, BMI= 31.18±0.92 kg/m2, and five subjects in group two, BMI= 36.94±2.25 kg/m2, ran on the treadmill with progressive intensities of 50, 60, 70 and 80% of VO2max for 10, 10, 5, and 2 min respectively. Blood samples were collected before the exercise (as the resting values), after each workload (during the exercise), and at 30, 60, and 120 min (during recovery).
Results: Plasma acylated ghrelin concentrations and hunger ratings in two groups were decreased and remained significantly lower than resting values (P=0.008 and P=0.002 respectively) at the end of the trial and there was no significant differences between groups. Growth hormone levels in two groups were increased and remained significant-ly higher than resting values (groups one P=0.012, group two P=0.005) at the end of the trial and there was no significant differences between groups. In addition, there were no significant differences between area under the curves (AUC) values over total periods for acylated ghrelin, hunger ratings, and growth hormone in two groups.
Conclusion: These findings indicate that individuals with two levels of obesity have the same response to the different intensities of treadmill running and two hours thereafter during recovery period, which can be considered for designing a more effective weighting loss training program.
