Navegando por Assunto "Treinamento resistido"

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Acesso aberto (Open Access)
Efeito da suplementação aguda de guaraná (Paullinia Cupana) e de uma dose equivalente de cafeína sobre parâmetros de potência muscular na execução do exercício supino reto
(Universidade Federal do Pará, 2024) COLAÇO, Fernando Sampaio; PENNA, Eduardo Macedo; http://lattes.cnpq.br/3746450308327976; https://orcid.org/0000-0003-0058-7967
Introduction: Guarana (Paullinia Cupana) is a natural substance rich in caffeine and other bioactive components. It is known that its acute ingestion can improve cognitive performance and effort perception parameters, but it is still unclear whether this ingestion can be efficient as an ergogenic substance in the production of muscular power, and whether this possible ergogenic effect is due to its caffeine concentration Objective: The objective of the present research was to compare the effect of acute ingestion of Guaraná (Paullinia Cupana) with an equivalent dose of caffeine on muscle power parameters. Methods: 34 individuals (18 to 35 years old) practicing resistance training were recruited and randomized into three experimental situations: PLACEBO (PLA); 500mg of guarana (GUA-500, containing 130mg of caffeine) and 130mg of caffeine (CAF-130). The individuals underwent a familiarization session with the bench press exercise performed on the Smith machine, in which the individuals' 1RM value and the optimal load for power production were measured. After a minimum interval of 48 hours from the 1RM test and optimal load, the individuals performed, on different days, the three experimental sessions in a randomized order: acute ingestion of caffeine, placebo or Guarana. Each experimental situation had a minimum washout interval of two days. A percentage of optimal load for power production was estimated through a progressive test on the bench press using only the bar, 30%, 40%, 50% and 60% of 1RM in order to identify the best load to perform 3 sets up to 40% of the loss of movement speed, with a 5-minute break between sets. Before performing the physical task, the individuals performed two sets of five repetitions using the load identified as optimal, with a 3-minute break between each set. warm-up series. Participants performed the concentric phase of movement performed at maximum intentional speed, and the eccentric phase lasting 2 seconds, in which the following variables were measured: average power (Watts), peak power (Watts), peak speed (m/s), and average propulsive speed (m/s). Results: Regarding the number of repetitions achieved between the experimental situations, no statistically significant difference was identified between the factors capsule ingested (F(2, 264) = 1.4689, P = 0.2320; partial η² = 0.01); between the three series performed (F(2, 264 = 0.5775, P = 0.5620) and in relation to Capsule: Series (F = 0.2937, P = 0.8819), in relation to Peak Power, the analyzes did not detect any significant effect on the values Capsule (F (2,264) = 0.0908; P = 0.7479), Series (F (2, 264) = 1.5053; P = 0.2238) and for the interactions Capsule: Series (F (4, 264) = 0.7674; P = 0.5453), regarding Average Power, the analysis did not detect significant effects for the Capsule factors (F (2, 264) = 0.028; P = 0.972; partial η² < 0.01), Series (F (2, 264) = 1.187; P = 0.306; partial η² < 0.01), and for the Capsule interaction: series (F (4,264) = 1.266; P = 0.283; partial η² = 0.02), as for Peak Speed, the analysis indicated no effect for the Capsule factor (F (2,263) = 1.162; P = 0.314; partial η² < 0.01), a significant effect for the factor Series (F (2, 263) = 3, 479; P = 0.03; partial η² = 0.03), in the Capsule:series interaction analysis (F (4, 263) = 1, 337; P = 0.256 ; partial η² = 0.02), no significant effect was identified. With regard to Average propulsive speed, no significant differences were identified for the factors Capsule (F (2, 264) = 0.401; P = 0.669; partial η² = 0.01), Series (F (2,264) = 1 , 327; P = 0.266; partial η² < 0.01) and for the Capsule: series interaction (F (4, 264) = 1.199; P = 0.311; partial η² < 0.01). Conclusion: Supplementation with 500mg of Guarana containing 130mg and 130mg of caffeine alone did not trigger any ergogenic effect on muscle power parameters and bench press speed.
Acesso aberto (Open Access)
Responsividade de parâmetros neuromusculares e capacidade funcional a dose mínima de treinamento resistido em mulheres de meia-idade e idosas
(Universidade Federal do Pará, 2023-04-24) NORONHA, Ádria Samara Negrão; COSWIG, Victor Silveira; http://lattes.cnpq.br/0097939661129545; https://orcid.org/0000-0001-5461-7119
Resistance training (RT) is an effective strategy to mitigate the loss of muscle strength and the risk of functional limitations that occur drastically after 55 years of age. However, there is evidence of inter-individual variations in responsiveness to resistance training, since some people can be responsive and others non-responsive to the same protocol. Thus, the objective of the present study was to verify the responsiveness of middle-aged and elderly women submitted to TR with a minimum dose approach and to verify the effect of the protocol on muscle strength and functional capacity of the participants. Twenty-two untrained women, mean age 64.3 ± 7.2 years, body mass 65.5 ± 9.2 kg, and height 152.3 ± 4.3 cm, randomly assigned to the Intervention Group (INT), submitted to the minimum dose protocol during 4 weeks, or to the Control Group (CON), who participated in two lectures and two stretching classes. The participants were evaluated for strength (1 repetition maximum in Leg Press 180º, Seated Rowing, and Straight Supine) and functional capacity (Timed Up and Go, Physical Performance Battery) before and at the end of the 4 weeks. For the statistical analysis it was performed the Analysis of Variance of repeated measures and Bonferroni post-hoc test for data with normal distribution, Mann Whitney U test for non-normally distributed data, Deltas of variation (Δ%) to present percentage of change and independent t test to compare the means of percentage of change between groups. The significance level adopted was p< 0.05. Levene's test was used to check the variance between groups. For classification of responsiveness, the standard deviation of the CON change score was multiplied by 1.96. Individuals outside this range were classified as High responders or Low responders. The results suggest 16.6% High responders in the 1RM of the straight supine and 8.4% in the estimated 1RM in the same exercise, with 25% High responders for average and peak velocity of the Sit and Stand test. Regarding the mean differences, we observed significant increases in muscle strength only for INT, with no differences between groups. Thus, it is concluded that 4 weeks of TR performed with a minimal dose approach presents a small rate of High responders for upper limb strength and lower limb speed. Furthermore, the training dose used seems to be insufficient to generate greater muscle strength and functional capacity adaptations than the control in middle-aged and elderly women.