Appetite Is Suppressed After Full-Body Resistance Exercise Compared With Split-Body Resistance Exercise: The Potential Influence of Lactate and Autonomic Modulation.

ABSTRACT: 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.

Autonomic modulation and its relation with body composition in swimmers.

This study compared autonomic modulation in swimmers and non-athletes in relation to body composition. A total of 28 athletes with a mean age of 19.7 ± 2.9 years were evaluated who had at least 2 years of swimming training, trained approximately 7,000 m per day, with a frequency of 5 days per week, and who competed at national level. The control group was made up of 21 volunteers (23.0 ± 2.5 years), who did not practice regular physical activity (<2 hours per week). Body composition was estimated using dual-energy x-ray absorptiometry, and autonomic modulation was assessed by heart rate variability (HRV). The results show that there were significant differences in autonomic modulation and body composition between the groups, and that the athletes had a higher overall variability (standard deviation of all normal intervals between consecutive heart beats [SDNN]: 78.1 [72.5-93.5] × 61.1 [56.4-75.7], p = 0.022) and greater autonomic balance (LF/HF: 0.96 [0.88-1.35] × 0.71 [0.56-0.93], p = 0.023), compared with the non-athletes, respectively. In addition, a moderate and positive relation was obtained between fat-free mass and the square root of the squared differences between consecutive heartbeat intervals (RMSSD: r = 0.526, p = 0.004 × r = 0.456, p = 0.038), (SDNN: r = 0.617, p = 0.001 × r = 0.571, p = 0.007) and low frequency (LFms: r = 0.517, p = 0.005 × r = 0.600, p = 0.004) in the athletes and non-athletes, respectively, without a correlation between fat mass (FM). The conclusion is that young highly trained swimmers had lower FM, increased fat-free mass, and better HRV than young adult non-athletes and suggests that a lower quantity of FM and, especially, a greater fat-free mass (FFM) are linked to better autonomic modulation. Thus, this study could contribute to coaches and trainers establishing greater performance by better autonomic modulation and greater quantity of FFM.

The Effects of combined aerobic and resistance training on heart rate variability in postmenopausal women / Efeitos do treinamento aeróbio e resistido combinados na variabilidade da frequência cardíaca em mulheres na menopausa

Model of the study: Controlled clinical trial. Objective: To verify the effects of 16 weeks of combined aerobic and resistance training on cardiac autonomic modulation in menopausal women. Methods: 17 menopausal women were divided into two groups: the training group (TG: n=11) and control group (CG:n=6). The body composition variables were estimated using dual-energy X-ray absorptiometry. The cardiac autonomic modulation was evaluated by heart rate variability using linear indexes. The training protocol consisted of 16 weeks of 50 minutes of resistance training and 30 minutes of aerobic training. Results: For the TG there was an increase in the rMSSD(ms) index (pre:17,4±3,7 and post:24,8±13,1,p<0,045), an increase in the duration of the intervals between the cardiac beats (ms) (pre:891,2±80,2 andpost:974,1±71,4, p<0,003) and in the values of heart rate (bpm) (pre:68,1±6,4 and post:62,0±4,7, p<0,003), additionally for the spectral indexes in normalized units, changes for LF (pre:52,2±13,1 and post:44,5±12,4, p<0,025) and HF (pre:47,8±13,3 and post:55,5±12,4, p<0,025) were noticed, demonstrating increased parasympathetic and reduced sympathetic. There were no significant differences to CG. Conclusion: combined aerobic and resistance training promoted benefits to the autonomic modulation in menopausal women.

Modelo do estudo: Ensaio clínico controlado. Objetivo: Verificar a resposta de 16 semanas do treinamento aeróbio e resistido combinado sobre a modulação autonômica em mulheres na menopausa. Métodos: 17 mulheres foram divididas em dois grupos: grupo treino (GT: n=11) e grupo controle (GC:n=6). As variáveis de composição corporal foram estimadas pela absorptiometria radiológica de dupla energia. A modulação autonômica foi avaliada pela variabilidade da frequência cardíaca usando índices lineares. O protocolo de treinamento consistiu em 16 semanas, por 50 minutos de treinamento resistido e 30 minutos de treinamento aeróbio. Resultados: Para o GT houve incremento do índice rMSSD (ms) (pre:17,4±3,7 e pos: 24,8±13,1, p<0,045), aumento dos intervalos entre batimentos cardíacos consecutivos (pre:891,2±80,2 e pos:974,1±71,4, p<0,003) e dos valores de frequência cardíaca (bpm) (pre:68,1±6,4 e pos:62,0±4,7, p<0,003), para os índices espectrais em unidades normalizadas, houve redução de LF (pre:52,2±13,1 e pos:44,5±12,4, p<0,025) e incremento de HF (pre:47,8±13,3 e pos:55,5±12,4, p<0,025).Não houve diferenças significantes para o GC. Conclusão: o treinamento aeróbio e resistido combinado promoveu benefícios sobre a modulação autonômica em mulheres na menopausa.