It may be that resistance exercise can be used to prevent the degenerative processes and inflammation associated with ageing. Thus, the aim of the present study was to evaluate the effects of resistance training on cytokines, leptin, resistin, and muscle strength in post-menopausal women. Thirty-five sedentary women (mean age 63.18 years, s = 4.8; height 1.64 m, s = 0.07; body mass 57.84 kg, s = 7.70) were recruited. The 16 weeks of periodized resistance training consisted of two weekly sessions of three sets of 6-14 repetition maximum. Maximal strength was tested in bench press, 45 degrees leg press, and arm curl. Plasma tumour necrosis factor-alpha, interleukin-6, interleukin-15, leptin, and resistin were determined by enzyme-linked immunosorbent assay. Maximal strength on all measures was increased after 16 weeks. There were minor or no modifications in tumour necrosis factor-alpha and interleukin-15. Interleukin-6 was decreased 48 h after compared with baseline and declined after 16 weeks. Leptin decreased 24 h after compared with baseline and was reduced at baseline and 48 h after compared with pre-training. There was a decrease in resistin after 24 and 48 h compared with baseline and a decline in baseline and immediately after levels compared with pre-training. A possible explanation of the results of the present study is a lower production of pro-inflammatory cytokines by the innate immune system. Periodized resistance training seems to be an important intervention to reduce systemic inflammation in this population.
The purpose of this study was to report and analyze the practices adopted by bodybuilders in light of scientific evidence and to propose evidence-based alternatives. Six (four male and two female) bodybuilders and their coaches were directly interviewed. According to the reports, the quantity of anabolic steroids used by the men was 500–750 mg/week during the bulking phase and 720–1160 mg during the cutting phase. The values for women were 400 and 740 mg, respectively. The participants also used ephedrine and hydrochlorothiazide during the cutting phase. Resistance training was designed to train each muscle once per week and all participants performed aerobic exercise in the fasted state in order to reduce body fat. During the bulking phase, bodybuilders ingested ~2.5 g of protein/kg of body weight. During the cutting phase, protein ingestion increased to ~3 g/kg and carbohydrate ingestion decreased by 10–20%. During all phases, fat ingestion corresponded to ~15% of the calories ingested. The supplements used were whey protein, chromium picolinate, omega 3 fatty acids, branched chain amino acids, poly-vitamins, glutamine and caffeine. The men also used creatine in the bulking phase. In general, the participants gained large amounts of fat-free mass during the bulking phase; however, much of that fat-free mass was lost during the cutting phase along with fat mass. Based on our analysis, we recommend an evidence-based approach by people involved in bodybuilding, with the adoption of a more balanced and less artificial diet. One important alert should be given for the combined use of anabolic steroids and stimulants, since both are independently associated with serious cardiovascular events. A special focus should be given to revisiting resistance training and avoiding fasted cardio in order to decrease the reliance on drugs and thus preserve bodybuilders’ health and integrity.
The aims were both to determine lactate and ventilatory threshold during incremental resistance training and to analyze the acute cardiorespiratory and metabolic responses during constant-load resistance exercise at lactate threshold (LT) intensity. Ten healthy men performed 2 protocols on leg press machine. The incremental test was performed to determine the lactate and ventilatory thresholds through an algorithmic adjustment method. After 48 h, a constant-load exercise at LT intensity was executed. The intensity of LT and ventilatory threshold was 27.1±3.7 and 30.3±7.9% of 1RM, respectively (P=0.142). During the constant-load resistance exercise, no significant variation was observed between set 9 and set 15 for blood lactate concentration (3.3±0.9 and 4.1±1.4 mmol x L(-1), respectively. P=0.166) and BORG scale (11.5±2.9 and 13.0±3.5, respectively, P=0.783). No significant variation was observed between set 6 and set 15 for minute ventilation (19.4±4.9 and 22.4±5.5 L x min(-1), respectively, P=0.091) and between S3 and S15 for VO2 (0.77±0.18 and 0.83±0.16 L x min(-1), respectively, P=1.0). Constant-load resistance exercise at LT intensity corresponds to a steady state of ventilatory, cardio-metabolic parameters and ratings of perceived exertion.
Resistance incremental tests (IT) make it possible to determine critical metabolic and cardiovascular changes, such as the lactate threshold (LT). Different methods are frequently used to improve the exactness of LT identification. The objective of the study was to identify LT by four different methods (visual inspection, log-log, algorithmic adjustment and QLac) during resistance exercise and to evaluate which methods present more precision. Twelve men performed a maximal IT on the leg press at relative intensities of 10%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70%, 80% and 90% of 1RM with 1-min stages. During the 2-min interval between stages, capillary blood was collected for blood lactate analysis. LT was detected using each of the four methods. The intensity of LT by visual inspection method was 26·9 (5·2)% of 1RM, adjustment algorithmic method was 27·8 (3·6)% of 1RM, log-log method was 23·3 (3·5)% of 1RM and QLac method was 31·6 (9·8)% of 1RM, with significant difference only between log-log and QLac methods. Bland and Altman analysis shows better concordance for visual inspection versus adjustment algorithmic methods. The visual inspection, algorithmic and log-log methods detected the LT at the same intensity. The mathematical models, specially the algorithmic method, provide more precision.
Both duration and intensity of exercise have an impact on the blood pressure response. Above 30% of 1RM, the SBP decreases in approximately 20 seconds and starts to increase until the end of the set of leg press exercise.
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