Marco Meucci

Dehydration and Acute Weight Gain in Mixed Martial Arts Fighters Before Competition

Abstract Jetton, AM, Lawrence, MM, Meucci, M, Haines, TL, Collier, SR, Morris, DM, and Utter, AC. Dehydration and acute weight gain in mixed martial arts fighters before competition. J Strength Cond Res 27(5): 1322–1326, 2013—The purpose of this study was to characterize the magnitude of acute weight gain (AWG) and dehydration in mixed martial arts (MMA) fighters before competition. Urinary measures of hydration status and body mass were determined approximately 24 hours before and then again approximately 2 hours before competition in 40 MMA fighters (mean ± SE, age: 25.2 ± 0.65 years, height: 1.77 ± 0.01 m, body mass: 75.8 ± 1.5 kg). The AWG was defined as the amount of body weight the fighters gained in the approximately 22-hour period between the official weigh-in and the actual competition. On average, the MMA fighters gained 3.40 ± 2.2 kg or 4.4% of their body weight in the approximately 22-hour period before competition. Urine specific gravity significantly decreased (p < 0.001) from 1.028 ± 0.001 to 1.020 ± 0.001 during the approximately 22-hour rehydration period. Results demonstrated that 39% of the MMA fighters presented with a Usg of >1.021 immediately before competition indicating significant or serious dehydration. The MMA fighters undergo significant dehydration and fluctuations in body mass (4.4% avg.) in the 24-hour period before competition. Urinary measures of hydration status indicate that a significant proportion of MMA fighters are not successfully rehydrating before competition and subsequently are competing in a dehydrated state. Weight management guidelines to prevent acute dehydration in MMA fighters are warranted to prevent unnecessary adverse health events secondary to dehydration.

Impacts of coordinative training on normal weight and overweight/obese children’s attentional performance

This study investigated the efficacy of a physical activity (PA) program to improve the attention span in normal weight vs. overweight/obese children. The study was designed as a cluster-randomized controlled intervention. One hundred fifty-seven normal weight and overweight/obese primary school children were randomly divided in three cohorts: Traditional PA, Coordinative PA and a Control group (not attending any PA). Before and after 5 months of intervention, children were administered the d2-R test of attention. Results showed that participants’ attentional performances were significantly affected by Time (pre vs. post; P < 0.01) and by Time × Group interaction (traditional vs. coordinative vs. control; P < 0.001), revealing significant different effects of intervention/exercise modality on children’s attentional performance, independently of their weight status. These data suggest that a 5-month school-based PA intervention can improve the cognitive performance in children. Further, the Coordinative PA intervention resulted in the most significant improvement in children’s attention.

Effects of Aerobic Exercise Based upon Heart Rate at Aerobic Threshold in Obese Elderly Subjects with Type 2 Diabetes

In obese diabetic subjects, a correct life style, including diet and physical activity, is part of a correct intervention protocol. Thus, the aim of this study was to evaluate the effects of aerobic training intervention, based on heart rate at aerobic gas exchange threshold (AerTge), on clinical and physiological parameters in obese elderly subjects with type 2 diabetes (OT2DM). Thirty OT2DM subjects were randomly assigned to an intervention (IG) or control group (CG). The IG performed a supervised aerobic exercise training based on heart rate at AerTge whereas CG maintained their usual lifestyle. Anthropometric measures, blood analysis, peak oxygen consumption (V˙O2peak), metabolic equivalent (METpeak), work rate (WRpeak), and WRAerTge were assessed at baseline and after intervention. After training, patients enrolled in the IG had significantly higher (P < 0.001) V˙O2peak, METpeak, WRpeak, and WRAerTge and significantly lower (P < 0.005) weight, BMI, %FM, and waist circumference than before intervention. Both IG and CG subjects had lower glycated haemoglobin levels after intervention period. No significant differences were found for all the other parameters between pre- and posttraining and between groups. Aerobic exercise prescription based upon HR at AerTge could be a valuable physical intervention tool to improve the fitness level and metabolic equilibrium in OT2DM patients.

Effects of supervised exercise program on metabolic function in overweight adolescents

BackgroundInactivity is a primary factor related to childhood obesity, yet aerobic exercise has been shown to prevent weight gain and improve fitness in adolescents. Moreover, children become less active during their summer break from school. This study compared the effects of 4 and 8 weeks of supervised summer activity versus an unsupervised summer break on metabolic function and fitness in adolescents.MethodsTwenty-two adolescents were divided into 4-week (n=6, weight 48.1±14.9 kg, body fat 27.4±8.4%) and 8-week exercise groups (n=6, weight 43.4±10.9 kg, body fat 28.5±12.8%), that performed supervised, play-based physical activity, versus an age-matched 8 week control group that maintained their typical summer break (n=10, weight 41.7±10.0 kg, body fat 23.7±8.0%). Anthropometrics, resting energy expenditure (REE), resting heart rate (RHR) and peak aerobic capacity (VO2peak) were evaluated before and after the intervention (4 or 8 weeks).ResultsREE showed group differences in posttraining conditions (the 4-week group vs. the control group, 1220±169 vs. 1067±144 kcal/die, and the 8-week group vs. the control group, 1202±151 vs. 1067±144 kcal/die, P=0.047), but RHR decreased (pre-program vs. post program: 97±22 vs. 80±8 beat/min, P=0.001) and VO2peak significantly increased (pre-program vs. post program: 27.8±7.8 vs. 34.8±6.5 mL/kg/min, P=0.001) in the 8-week group compared to the control group.ConclusionsEight weeks of supervised play-based activity increased REE and VO2peak in adolescents with concomitant decreases in RHR. These data suggest that this novel model of exercise prescription could be considered world-wide by clinicians to improve fitness base in adolescents and help to combat the growing epidemic of childhood obesity.

Whole body vibration: unsupervised training or combined with a supervised multi-purpose exercise for fitness?

Abstract The aim of the study was to compare the effect of an unsupervised whole body vibration (WBV) training and two different supervised multi-purpose exercise programmes, with and without WBV, on body composition, functional fitness and self-reported well-being in middle-aged adults. Fifty-four healthy participants (age 48.6 ± 6.7 years) were randomly assigned to a vibration group (VG), a multi-purpose exercise group (MG) and a multi-purpose exercise with vibration group (VMG) and trained 3 days a week for 4 months. VG performed a standardised unsupervised WBV protocol, MG a supervised multi-purpose exercise and VMG a multi-purpose exercise including vibration. After training, drop out was significantly higher in VG group (P = 0.016) when compared to VMG group. In both MG and VMG, body composition, sit-up, push-up, sit and reach, agility test, hopping test and self-reported general health significantly improved (P < 0.05). No additive effects were generated by the vibration stimulus. Percentage of body fat and agility test in VG had a significant opposite trend compared to VMG group (P < 0.05). In summary, an unsupervised WBV training should not be chosen for training protocol. However, positive effects on physical fitness and the best results in adherence could be achieved integrating WBV practice into a multi-purpose exercise training.

Effect of play‐based summer break exercise on cardiovascular function in adolescents

To compare the effects of 4 and 8 weeks of play‐based, supervised exercise during summer break versus an unsupervised break on cardiovascular function in adolescent children.

Psychophysiological responses to Salsa dance.

Speculation exists whether dance provides physiological stimuli adequate to promote health and fitness benefits. Unfortunately, research to date has not addressed the affective and exertional responses to dance. These responses are of interest as positive affective and exertional responses experienced during physical activity may play an important role in predicting adherence. The present study aims to examine the psychophysiological responses of different Salsa dance styles. Ten pairs of dancers performed two different structured lessons of Salsa dance, including Typical Salsa and Rueda de Casino lessons, and a non-structured Salsa dance at a night club. Physiological responses (i.e., percent of heart rate reserve; %HRR) were continuously assessed and perceived exertion and affective valence were rated every 15 min throughout the trials. %HRR responses differed between the Salsa dance styles (%HRR from 41.3 to 51.9%), and participants were dancing at intensities near their ventilatory threshold. Specifically, Typical Salsa lesson elicited lower %HRR responses than Rueda de Casino lesson (p < 0.05), but similar %HRR responses to Salsa dance at a night club condition (p > 0.05). Surprisingly, exertional (from 8 to 11) and affective (from +3 to +5) responses were unaffected by Salsa dance styles (p > 0.05). These data support that different Salsa dance styles provide physiological stimuli adequate to promote health and fitness benefits, and perhaps more importantly, produce pleasurable experiences, which in turn might lead to an increase in adherence to Salsa dancing which likely provides exercise-like health benefits.

Effects of combined physical education and nutritional programs on schoolchildren's healthy habits.

Background. A multidisciplinary approach seems to be effective in creating healthy habits in children. The aim of this study was to evaluate the efficacy of three 5-month combined physical education (PE) and nutritional interventions on body composition, physical activity (PA) level, sedentary time and eating habits of schoolchildren. Methods. Anthropometric data, weekly PA level, sedentary time and eating habits of 230 healthy students were analysed using a repeated-measures ANOVA with Group (experimental group 1 vs experimental group 2 vs control group), Adiposity Status (under fat vs normal fat vs obese), and Time (pre vs post) as factors. Results. Body fat mass percentage increased after intervention (18.92 ± 8.61% vs 19.40 ± 8.51%) in all groups. The weekly PA level significantly increased after intervention in both experimental groups. Sedentary time significantly decreased after the intervention period (565.70 ± 252.93 vs 492.10 ± 230.97 min/week, p < 0.0001). Moreover, obese children were more sedentary than under fat and normal fat children. Children significantly changed the consumption of some specific foods after intervention. Discussion. This study revealed the effectiveness of a combined PE and nutritional intervention to improve children’s healthful dietary practices and to encourage an active lifestyle. However, it needs a further appropriate development to establish patterns of healthful dietary practices that encourage an active lifestyle with which to maintain healthy habits through life.

Metabolomic Shifts Following Play-Based Activity in Overweight Preadolescents

BACKGROUND Play-based activities can be a positive intervention to increase participation of overweight children. Metabolomics can reveal elemental shifts in the metabolome, lending to potential mechanistic explanations behind improvements in physiological systems. OBJECTIVE To elucidate dose-response urinary metabolomic signature shifts in overweight preadolescents following four or eight weeks of supervised play-based activity versus a typical summer break control group. We hypothesized that eight weeks of activity would cause the greatest shift in the metabolites. STUDY DESIGN Twenty-two recreationally active preadolescents (12 males, 10 females) were randomly assigned to a four-week (4w) or eight-week (8w) activity group or to a control group (C). Participants reported to the laboratory on two separate occasions during which descriptive characteristics were recorded and urine samples were obtained. Children in the 4w and 8w cohort were tested at the beginning and end of the four and eight weeks of a supervised play-based physical activity program where they were active for 6 hours a day, 5 days a week. Children in the C group were tested before and after eight weeks of an unsupervised summer break. RESULTS A valid supervised partial least squares discriminant analysis model was obtained between post-exercise subjects in 8w and C (3 components, R2X = 0.332, R2Y = 0.976, Q2 = 0.091). The eight week intervention yielded significant metabolomic changes in several identified compounds. CONCLUSION When compared to a typical unsupervised summer break, a supervised play-based intervention provides enough of a stimulus for a shift in the metabolome.

P-25 Substrates oxidation at high intensity exercise in sedentary females

Objectives The substrates utilisation at high intensity exercise has been less studied and intensity at which carbohydrates (CHO) remain single energy source while fat utilisation becomes negligible (FATmin), is debatable 4. Since physical activity in aerobic fat burn zone is prescribed to facilitate improvement of fat oxidation and insulin sensitivity while improving health 1, activity equal or above FATmin can’t be considered as beneficial. Therefore, FATmin could become important exercise parameter in sedentary population. The aim of this study was to determine FATmin while performing incremental treadmill test till exhaustion and to assess its correlation with anaerobic threshold (AT), which in turn can be used as an individuals performance marker or last exercise beneficial point. Methodology Thirteen sedentary females (age: 34 ± 3 y, body mass: 62 ± 4 kg, height: 165 ± 4 cm) performed breath-by-breath test to measure maximal oxygen uptake (VO2max;ml·kg-1·min-1) and substrates oxidation (g·min-1). A Pearson correlation coefficient (r), 95% confidence interval (CI) and effect size (R2 ) were used to test connexion between VO2 at AT and at FATmin. Alpha intervals were set at p < 0.05. Substrates oxidation was calculated using a stoichiometric equation 4. The AT was detected by V-slope method 2. Results VO2max was 34.89 ± 4.34 ml·kg-1·min-1 (95% CI 34.02 to 35.52). FATmin and AT occurred at 24.53 ± 4.25 ml·kg-1·min-1 VO2 (95% CI 24.29 to 24.97) and 24.04 ± 4.07 ml·kg-1·min-1 VO2 (95% CI 24.01 to 24.80), respectively. A high correlation was found between VO2 at FATmin and at AT (r = 0.91, p < 0.001, 95 % CI of 0.87 to 0.93). R2 was 0.83. Absolute fat oxidation rate at FATmin was 0.01 ± 0.01 g·min-1 (95% CI 0.00 to 0.01). Conclusions This is the first study to detect FATmin and demonstrate correlation between VO2 at FATmin and at AT in sedentary females. High inter-subjects FATmin variation demonstrates marked degree of individuality and importance of existing correlation should be taken into consideration when aiming to optimise exercise prescription for sedentary population. References American College of Sports Medicine: Position Stand. “The Recommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness”. Med Sci Sports Exerc 1998;30:975–991. Beaver WL, Wasserman K, Whipp BJ. A new method for detecting anaerobic threshold by gas exchange. J Appl Physiol 1986;60(6):2020–2027. Elia M, Livesey G. Energy expenditure and fuel selection in biological systems: the theory and practice of calculations based on indirect calorimetry and tracer methods. World Rev Nutr Diet 1992;70:68–131. Peric R, Meucci M, Nikolovski Z. Fat utilisationutilization during high intensity exercise: when does it end? Sport Med Open 2016;2(35). DOI: 10.1186/s40798-016-0060-1