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Conrado de Freitas, M, Ricci-Vitor, AL, de Oliveira, JVNS, Quizzini, GH, Vanderlei, LCM, Silva, BSA, Zanchi, NE, Cholewa, JM, Lira, FS, and Rossi, FE. Appetite is suppressed after full-body resistance exercise compared with split-body resistance exercise: the potential influence of lactate and autonomic modulation. J Strength Cond Res 35(9): 2532-2540, 2021-The purposes of this study were to investigate the effects of full- vs. split-body resistance training on appetite and leptin response and to verify the potential involvement of lactate and autonomic modulation during this response in trained men. Twelve recreationally resistance-trained men (age = 26.1 ± 5.5 years) performed 3 randomized trials in 3 conditions: upper body (UB), lower body (LB), and full body (FB). The subjective rating of hunger was obtained through a visual analog scale. Leptin and lactate concentration were evaluated at rest, immediately after exercise, and during recovery. Heart rate variability in the time and frequency domains was recorded at baseline and during recovery (until 60 minutes after exercise) to assess autonomic modulation. The FB condition induced lower subjective hunger ratings than the UB at Post-1 hour (p < 0.05) and a significant difference in the area under the curve between conditions (p = 0.028) with lower hunger sensation for FB in relation to UB (p = 0.041). The FB presented greater lactate concentration and induced slower heart rate variability recovery in relation to UB and LB conditions (p < 0.05), and heart rate variability remained lower until 60 minutes after exercise compared with rest only in the FB condition. There was a significant negative correlation between subjective hunger ratings and lactate concentration only for the FB condition (r = -0.72, p = 0.028). Full-body resistance exercise induced lower subjective hunger ratings after exercise in relation to UB resistance exercise. The FB also induced higher lactate production and slower recovery of autonomic modulation compared with the UB and LB conditions. Future research is necessary to investigate a mechanistic relationship between lactate concentrations and hunger suppression after resistance exercise. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of heavy back squat (90% one repetition maximum [1RM]) postactivation potentiation (PAP) on acute resistance exercise performance and force production in recreationally trained men, and to verify the relationship between maximal strength and the PAP response. Ten resistance-trained men randomly completed 4 experimental trials: (a) back squats without PAP (No-PAP), (b) back squats with PAP, (c) maximum voluntary isometric contraction (MVIC) of the quadriceps without PAP, and (d) MVIC with PAP. Back squats were performed with 4 sets at 70% of 1 RM with 2 minutes of rest interval. The number of squats repetitions performed was recorded for each set, and a total number of repetitions were calculated to analyze performance. Maximum voluntary isometric contraction was measured using electronic dynamometer, and the peak force and mean force were recorded. Blood lactate concentration was analyzed presquat and postsquat exercise. Repetitions performed in the first set was significantly (p, 0.001) greater in the PAP condition (22.00 6 5.14) compared with No-PAP (15.50 6 5.10), which resulted in significantly (p = 0.001) more total repetitions performed in the PAP (56.20 ± 17.3) condition compared with No-PAP (48.80 ± 14.5). Maximum voluntary isometric contraction peak was higher in PAP than in No-PAP (PAP = 765.7 ± 147.8 vs. No-PAP = 696.8 ± 131.5 N, p = 0.006). No significant correlations were observed between back squat 1RM relative to body mass and the PAP response in squat and MVIC. There were no significant differences in lactate concentration between conditions. In conclusion, PAP resulting from a heavy load prior back squat exercise improved total volume during resistance exercise. In addition, PAP was effective to increase force production during MVIC, but there was no relationship between relative 1RM values and the PAP response in trained men. [ABSTRACT FROM AUTHOR]

Intense aerobic exercise seems to increase serum concentrations of brain-derived neurotrophic factor (BDNF) in conjunction with increasing lactate; however, less is known about the BDNF response to differing resistance exercise protocols. We hypothesized that full-body (FB) resistance exercise will elicit a greater increase in serum BDNF and lactate compared with split-body resistance exercise. Twelve recreationally resistance-trained men (age = 25.3 6 5.9 years) performed 3 randomized trials of 18 sets of exercise: upperbody (UB), lower-body (LB), and FB conditions. Serum BDNF levels were assessed at rest, immediately Post-exercise, Post-1 hour, and Post-2 hours during recovery. Lactate concentration was evaluated at rest, after 9 sets, Post-exercise, Post-5, Post- 10, and Post-30 minutes during recovery. In addition, interleukin (IL-6 and IL-10) and the IL-6/IL-10 ratio were calculated. Lactate concentration and total volume were greater in the FB condition compared with LB and UB (p, 0.05). For BDNF, effect sizes were largest in the LB (1.4), followed by the FB (0.75), and moderate to UB (0.33), although no significant differences were observed between conditions. There was a statistically significant relationship between lactate and BDNF only for LB condition (rho = 0.72; p = 0.013). There were a greater IL-10 Post-1 hour for FB condition compared with UB and LB (p, 0.001), and lower IL-6/IL-10 ratio in FB compared with UB (p, 0.001). Lower body induced a great BDNF response, and FB resistance exercise elicited a greater increase of serum cytokines than UB in trained men. We speculate that the volume of work performed by larger muscles has a larger influence on BDNF than overall volume. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the acute effect of adenosine-5'-triphosphate (ATP) supplementation on performance and physiological responses during resistance exercise in recreationally resistance-trained males. Eleven men (age = 27.5 ± 5.5 years, mass = 83.4 ± 9.8 kg, height = 182 ± 0.04 cm) completed 2 randomized, double-blind trials: ATP supplement condition (ATP = 400 mg) or a placebo condition. Thirty minutes after supplement consumption, subjects performed 4 sets of half-squats until momentary muscular failure at 80% of the 1 repetition maximum with 2 minutes of recovery between sets. The total number of repetitions, blood pressure, heart rate, blood lactate, and oxygen consumption were evaluated. The total weight lifted were higher for the ATP condition compared with placebo (Placebo = 3,995.7 ± 1,137.8, ATP = 4,967.4 ± 1,497.9 kg; p = 0.005). Heart rate was higher at set-4 for ATP compared with placebo (p < 0.001) and oxygen consumption during exercise was greater for ATP (p = 0.021). There were no differences between conditions for lactate and blood pressure. In summary, a single oral dose of ATP supplementation improved lower-body resistance training performance and energy expenditure in recreational resistance-trained males. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance, rate of perceived exertion (RPE), and blood lactate concentrations during short-duration running in physically active adults. Ten physically active men (age = 23.5 ± 1.9 years, mass = 78.3 ± 12.4 kg, and height = 177.9 ± 5.9 cm) completed 2 randomized, double-blind trials: Capsaicin condition (12 mg) or a placebo condition. Forty-five minutes after supplement consumption, the participants performed a 1,500-m running time trial. Time (in seconds) was recorded. Blood lactate concentration was analyzed at rest, immediately after exercise, after 5, 10, and 30 minutes during recovery and the RPE was collected after exercise. The time was significantly (t = 3.316, p = 0.009) lower in the capsaicin (371.6 ± 40.8 seconds) compared with placebo (376.7 ± 39 seconds). Rate of perceived exertion was significantly (t = 2.753, p = 0.022) less in the capsaicin (18.0 ± 1.9) compared with the placebo (18.8 ± 1.3). Lactate increased across time for both conditions without significant differences between (p > 0.05). In summary, acute capsaicin supplementation improves middle distance running (1,500 m) performance and reduced RPE in physically active adults. [ABSTRACT FROM AUTHOR]

The relationship between immunometabolic response and performance is not well understood. This study evaluated the influence of concurrent strength and high-intensity aerobic sequence of exercise order between sessions on strength performance, metabolic, and inflammatory response. Eleven recreational weightlifters underwent the following 2 randomized sessions: (a) strength-aerobic exercise order (SA) and (b) aerobic-strength exercise order (AS). Blood samples were collected before (Pre) and immediately after the first exercise (Post-1) and the second exercise (Post-2) of each session. The SA condition presented a higher number of repetitions (SA: 54 ± 15 vs. AS: 43 ± 12) and total volume (SA: 7,265 ± 2,323 vs. AS: 5,794 ± 1846 kg) than the AS condition (both p = 0.001). Glucose was higher in Pre when compared with post-1 in both orders (p ≤ 0.05); changes in lactate were time-dependent in the different orders (p ≤ 0.05); however, AS post-2 lactate was lower when compared with SA post-2 (p ≤ 0.05). Interleukin-6 levels showed time-dependent changes for both exercise orders (p ≤ 0.05). Tumor necrosis factor alpha (TNF-α) level was increased only in AS post-1 (AS: pre = 21.91 ± 35.47, post-1 = 26.99 ± 47.69 pg·m-1 vs. SA: pre = 25.74 ± 43.64, post-1 = 29.74 ± 46.05 pg·ml-1, p ≤ 0.05). These results suggest that concurrent training order exhibits different immunometabolic responses and, at least in part, can be associated with the acute decline in strength performance induced by concurrent exercise. Our results point to a possible role of TNF-α (post-1 AS condition) as a trigger to restore the energy demand by providing substrates to help maintain contractile activity in skeletal muscle. [ABSTRACT FROM AUTHOR]