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An innovative moderate-intensity resistive exercise-training (RT) program was tested in thirty-five sarcopenic elders (SAR). The subjects were randomized into two groups: SAR training (SAR-RT), n = 20, 73.0 &plusmn, 5.5 years, or SAR non-training (SAR-NT), n = 15, 71.7 &plusmn, 3.4 years. The training consisted of 12-week progressive RT, thrice/week, at 60% one-repetition maximum (1RM), 3 sets, 14&ndash, 16 repetitions for both upper and lower limbs. The pre and post intervention measurements included: the skeletal muscle index (SMI%), strength (1RM), stair-climbing power (SCP), muscle thickness (MT) of vastus lateralis (VL) and elbow flexors (EF), VL pennation angle (PA), rectus femoris (RF) anatomical cross-sectional area (ACSA), reactive oxygen species (ROS), total antioxidant capacity (TAC), protein carbonyls (PC), thiobarbituric acid-reactive substances (TBARS), 8-isoprostane (8-iso-PGF2-&alpha, ), 8-OH-2-deoxyguanosine (8-OH-dG), as markers of oxidative stress/damage (OxS). In SAR-RT, SCP increased by 7.7% (P &lt, 0.01), MT increased by 5.5% for VL, 10.4% for EF and PA increased by 13.4% for VL (P &lt, 0.001 for all). The RF ACSA increased by 14.5% (P &lt, 0.001). 1RM significantly increased by at least 67% for all muscles tested. Notably muscle strength (1RM) positively correlated (P &lt, 0.001) with TAC and negatively with PC (P &lt, 0.001). In conclusion, moderate intensity RT is an effective strategy to increase muscle mass and strength in SAR, while minimizing OxS.

Among all nonpharmacological treatments, aerobic or resistance training (RT) has been indicated as a significantly important strategy to control hypertension. However, postexercise hypotension responses after intensity alterations in RT are not yet fully understood. The purpose of this study was to compare the outcomes of differing intensities of RT on hypertensive older women. Twenty hypertensive older women participated voluntarily in this study. After a maximum voluntary contraction test (one repetition maximum) and determination of 40% and 80% experimental loads, the protocol (3 sets/90″ interset rest) was performed in a single session with the following exercises: leg press, leg extension, leg curl, chest press, elbow flexion, elbow extension, upper back row, and abdominal flexion. Systolic and diastolic blood pressures were evaluated at rest, during exercise peak, and after 5, 10, 15, 30, 45, and 60 minutes of exercise and compared to the control. Both experimental loads were effective (P, Video abstract

Background Creatine (Cr) supplementation has been widely used among athletes and physically active individuals. Secondary to its performance-enhancing ability, an increase in oxidative stress may occur, thus prompting concern about its use. The purpose of this study is to investigate the effects of Cr monohydrate supplementation and resistance training on muscle strength and oxidative stress profile in healthy athletes. Methods A randomized, double-blind, placebo-controlled method was used to assess twenty-six male elite Brazilian handball players divided into 3 groups: Cr monohydrate supplemented group (GC, N = 9), placebo group (GP, N = 9), no treatment group (COT, N = 8) for 32 days. All subjects underwent a resistance training program. Blood samples were drawn on 0 and 32 days post Cr supplementation to analyze the oxidative stress markers, thiobarbituric acid reactive species (TBARS), total antioxidant status (TAS), and uric acid. Creatine phosphokinase, urea, and creatinine were also analyzed, as well. Fitness tests (1 repetition maximum - 1RM and muscle endurance) were performed on the bench press. Body weight and height, body fat percentage (by measuring skin folds) and upper muscular area were also evaluated. Statistical analysis was performed using ANOVA. Results Only GC group showed increase in 1RM (54 ± 9 vs. 63 ± 10 kg; p = 0.0356) and uric acid (4.6 ± 1.0 vs. 7.4 ± 1.6 mg/dl; p = 0.025), with a decrease in TAS (1.11 ± 0.34 vs. 0.60 ± 0.19 mmol/l; p = 0.001). No differences (pre- vs. post-training) in TBARS, creatine phosphokinase, urea, creatinine, body weight and height, body fat percentage, or upper muscular area were observed in any group. When compared to COT, GC group showed greater decrease in TAS (−0.51 ± 0.36 vs. -0.02 ± 0.50 mmol/l; p = 0.0268), higher increase in 1RM (8.30 ± 2.26 vs. 5.29 ± 2.36 kg; p = 0.0209) and uric acid (2.77 ± 1.70 vs. 1.00 ± 1.03 mg/dl; p = 0.0276). Conclusion We conclude that Cr monohydrate supplementation associated with a specific resistance program promoted a meaningful increase in muscle strength without inducing changes in body composition. The observed significant increase in uric acid and the decrease in TAS suggest that creatine supplementation, despite promoting acute effects on muscle strength improvement, might induce oxidative stress and decreases total antioxidant status of subjects.