Influence of Physically Active or Sedentary Lifestyle on Postural Control of Community-dwelling Old Adults

Objectives: The maintenance of the postural balance is fundamental for the daily living activities, as well as for the practice of physical exercise. However, the aging process and sedentary behavior (i.e., large sitting time) lead to changes biological systems, impairing postural balance with consequent increased falls risk. On the other hand, physical activity practice is a protective factor against these trends. The aim of this study is to investigate the influence of physical activity profile and sedentary behavior on postural control in community-dwelling old adults.Methods: This is a cross-sectional study including 208 community-dwelling old adults, which were stratified as sufficiently or insufficiently physically active and with or without sedentary behavior. Then, they were grouped as follow: G1 (sufficiently physically active and without sedentary behavior), G2 (insufficiently physically active, but without sedentary behavior), G3 (sufficiently physically active, but with sedentary behavior), and G4 (insufficiently physically active and with sedentary behavior).Results: Stabilometric parameters (sway area, total length of center of pressure [CoP] trajectory, and the mean velocity of CP displacement) were obtained to evaluate the postural control. There was significant difference between G1 and G4 on mean velocity of CoP displacement (p < 0.05).Conclusions: The coexistence of sedentary behavior and insufficient physically active profile seem to impact negatively on postural control.

Influence of Counter Movement Jump Session with Different Rest Intervals on Muscle Damage and Soreness

Objectives: Plyometrics has been used in sports training and many aspects of this modality are poorly understood. This study measures the magnitude of variations of serum creatine kinase (CK) activity and perceived muscle soreness after one session of Countermovement Jump (CMJ) session and compares 1 and 3 minutes rest intervals between each sets.Methods: A group of 30 young male was dividing in two groups and performed ten sets of ten CMJ with 1 or 3 minutes rest interval between sets. Before and after session (24, 48, and 72-h) they informed the muscle soreness perception and blood samples were collected for dosage of serum CK activity. Two (time) x Two (treatment) ANOVA was used to test differences in serum CK activity and muscle soreness. The alpha level was set at 0.05.Results: Serum CK activity measured 48 h after session augments ~2 and ~1.5 times in 1 min and 3 min rest interval respectively. No significant difference between groups that rests 1 or 3 minutes between sets was found. Muscle soreness rises 24 h after session without significant differences between groups.Conclusions: The findings show that the CMJ increases perceived muscle soreness and increases the serum CK activity, and the intervals of rest do not modulate these variables.

Is an Exercise Intervention the only way to Reduce Visceral Fat without Reducing Fat-free Mass in Children and Adolescents?

Objectives: To maintain proper development, it is recommended that children/adolescents focus more on increasing physical activity than dietary restriction when treating obesity. In other words, adults are better able to tolerate the reductions in fat-free body mass that often occur when trying to lose fat mass. In contrast, children and adolescents should avoid losses in fat-free mass in order to ensure proper development. Therefore, when trying to reduce visceral fat in children via a negative energy balance (i.e., exercise with or without calorie restriction), it is necessary to set desirable conditions in order to minimize the loss of fat-free mass. To determine whether this is possible, we reviewed literature discussing the relationship between changes in visceral fat obtained by abdominal imaging and changes in total body fat and fat-free mass after exercise training with and without calorie restriction in children and adolescents.Methods: Literature review.Results and Conclusions: Previous work found no reduction in fat-free mass in the exercise interventions in which there was no dietary-induced calorie restriction. This supports the idea that reducing visceral fat by increasing physical activity is the preferred strategy over dietary restriction in children and adolescents. Although factors such as the type (e.g. aerobic and/or resistance) of exercise and the amount (i.e. energy expenditure) of exercise will likely have an effect on the magnitude of change in intra-abdominal visceral fat, the quantity of each that is needed without reducing fat-free mass is currently unknown.

Provisional Designation of the Interleukin-6 Receptor (IL-6R) as a Novel Marker Gene for Exercise Tolerance

Objectives: Genomic markers linked to exercise-associated health benefits and/or sporting performance are increasingly used to guide decision-making in healthcare and sport/exercise science. This project investigated whether the IL-6R SNP “rs2228145” might be provisionally designated a novel physical activity/exercise marker. rs2228145 results in an Aspartate358/Alanine358 change adjacent to the site where the IL-6R protein is cleaved into two fragments, resulting in ~two-fold increases in blood-borne levels of soluble IL-6R [‘sIL-6R’].Methods: Cohorts of staff/students at Cardiff Metropolitan University donated/completed: [i] finger-prick capillary blood samples (subjected to ELISAs for sIL-6R, the associated signalling protein sgp130, and the IL-6/sIL-6R complex); [ii] cheek-swab samples containing buccal epithelial cell DNA (subjected to PCR-based IL-6R/rs2228145 genotyping assays); [iii] International Physical Activity Questionnaires (to estimate physical activity levels in the week preceding sample donation).Results: As expected, we observed significant genotype-dependent differences in blood-borne sIL-6R levels (CC (44.1±21.7ng/mL) vs. AC (28.6±7.3ng/mL) vs. AA (19.9±6.5ng/mL; P<0.05)); Importantly, AA homozygotes undertook significantly more physical activity than AC heterozygotes (6318±899 v. 3904±2280 MET-mins/week; P<0.01). Genotype was significantly associated with physical activity levels (P<0.05), and sIL-6R (P=0.197) and sgp130 (P=0.160) showed non-significant correlations with physical activity levels.Conclusions: These data suggest that IL-6R/rs2228145 genotype may influence participation in physical activity/exercise, perhaps by impacting on abilities to tolerate activity without experiencing adverse-effects. Although more research is required to confirm these preliminary findings, designation of IL-6R/rs2228145 as a novel marker, and determination of participants’ IL-6R/rs2228145 genotypes, may in future be useful tools to aid exercise-providers in designing personalised exercise programmes matched to clients/patients.