Jainara Lima Menezes

Paralympic Powerlifting is a maximal strength sport that requires high training intensity and efficient recovery to maintain performance and prevent injury. Intense training can induce oxidative stress, potentially compromising performance and physiological adaptation. Caffeine (CA) is a widely used ergogenic aid with potential to enhance muscle strength and reduce oxidative damage. This study investigated the acute effects of CA supplementation (9 mg/kg) on static strength indicators and oxidative stress markers in 14 male Paralympic powerlifting athletes. The protocol included two conditions (CA and placebo), with athletes performing 5 sets of 5 repetitions at 80% of 1 RM in the adapted bench press. Strength variables (maximal isometric force, 1-s peak force, and force variability) and biomarkers (TBARS/MDA, total antioxidant capacity, sulfhydryl groups, and uric acid) were analyzed. CA supplementation significantly increased maximal isometric strength, improved 1-s peak force, and reduced variability, suggesting enhanced motor unit recruitment. However, CA also led to increased oxidative stress, as evidenced by elevated TBARS levels, reduced antioxidant capacity, decreased sulfhydryl groups, and higher uric acid concentrations post-exercise. In conclusion, while CA acutely improves neuromuscular performance, it does not attenuate—and may even exacerbate—exercise-induced oxidative stress. Therefore, its use in strength sports should be approached with caution.

Exercise, including resistance exercise with high loads, has positive hemodynamic responses such as reduced systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), Pressure Product Rate (PPR), and estimated myocardial oxygen volume (MVO₂). Caffeine (CA), used to improve performance, tends to interfere with BP and HR. This study aimed to analyze the effects of CA supplementation on hemodynamic indicators in Paralympic weightlifting (PP). The exercise was performed on 14 male athletes (32.4 ± 8.5 years; 81.7 ± 21.9 kg) for three weeks. Two conditions were evaluated: supplementation with CA Anhydrous 9 mg/kg and with placebo (PL). The adapted bench press was used, with 5 × 5 at 80% 1RM. We evaluated BP, HR, PPR, and MVO₂, before, after, 5, 10, 20, 30, 40, 50, 60 min, and 24 h later. The CA presented higher absolute values in the pressure indicators than the PL, and after 24 h there was an inversion. The HR was higher in the CA and showed a reduction after 10 min. The PPR and MVO₂ in the CA presented absolute values greater than the PL, and 24 h later there was an inversion. There was no hypotensive effect, but the use of CA did not present risks related to PPR and MVO₂, demonstrating the safe use of this supplement in adapted strength sports.

Background: Paralympic powerlifting (PP) is one of the sports modalities that uses strength training with high loads, causing various physiological responses resulting from hemodynamic adaptations. Objective: To evaluate hemodynamic responses after traditional (TT) and eccentric (ET) training sessions in PP athletes. Methods: Twelve national-level PP athletes, aged: (Mean ± SD) 30.8 ± 10.05 years; 70.0 ± 16.1 kg. In the intervention, five sets of five repetitions (5 × 5) of the bench press at 80% of 1 repetition maximum (1RM) were used; in the TT and in the ET, 5 × 5 of the bench press with a load in the eccentric phase of 110% and that in the concentric phase of 80% of 1RM were used. Results: Compared to baseline, heart rate was significantly elevated at various times in the ET, between before and 20 min after (p = 0.023), and 40 min after (p = 0.035), but decreased to baseline in 24 h (p = 0.043, η2p = 0.395). In addition, the product pressure rate in the ET had a decrease between the moments before and 60 min after (p = 0.042), and before and 24 h after (p = 0.043). A high effect on myocardial oxygen volume in ET at 24 h was found (p = 0.018; η2p = 0.393). Conclusions: One session of traditional and eccentric training methods can be effective in causing significant changes in the cardiovascular system in PP athletes.

Background: Spinal cord injury (SCI) is a condition that affects the central nervous system, is characterized by motor and sensory impairments, and impacts individuals’ lives. The objective of this study was to evaluate the effects of resistance training on oxidative stress and muscle damage in spinal cord injured rats. Methodology: Forty Wistar rats were selected and divided equally into five groups: Healthy Control (CON), Sham (SHAM) SCI Untrained group (SCI-U), SCI Trained group (SCI- T), SCI Active Trained group (SCI- AT). Animals in the trained groups were submitted to an incomplete SCI at T9. Thereafter, they performed a protocol of resistance training for four weeks. Results: Significant differences in muscle damage markers and oxidative stress in the trained groups, mainly in SCI- AT, were found. On the other hand, SCI- U group presented higher levels of oxidative stress and biomarkers of LDH and AST. Conclusion: The results highlight that resistance training promoted a decrease in oxidative stress and a significative response in muscle damage markers.