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1.
Sports Med Int Open ; 8: a21816798, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38312926

RESUMO

We investigated the potential for publication bias in the field of sports science regarding studies on ergogenic aids and their effects on exercise performance. We found evidence to suggest that journals tend to prioritize studies with positive results (76%) while neglecting those with negative outcomes (2.7%). Worryingly, this could lead to a discrepancy between reported conclusions and actual study outcomes. We also identified inconsistencies between reported outcomes and actual performance variable outcomes. Taken together, these data highlight the need for future research to reduce bias and encourage the publication of studies with both positive and negative results to improve the reliability of scientific evidence in this field.

2.
Front Sports Act Living ; 5: 1257007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808161

RESUMO

Was investigated ergogenic aids (EAs) used by Brazilian athletes and their association with performance, sex, sports classification, and modality. It identified the main purposes of EAs and their prescription. Methods: 239 athletes of 15 modalities, ranging from regional to international level, answered a survey online. Results: Highly competitive athletes consumed nutritional and mechanical aids more (OR = 1.96 CI 95% [1.28-2.9]; OR = 1.79 CI 95% [1.29-2.47]), while the use of psychological EAs decreased [OR = 1.66 95% CI (1.18-2.94); p = 0.001]. Male athletes [OR = 1.44 CI 95% (1.11-2.88)] and individual sports practitioners [OR = 1.78 CI 95% (1.02-3.11)] used nutritional aids more. Triathlon athletes had higher nutritional EA use, while soccer athletes had lower. Combat sports athletes had higher pharmacological EA use. Conclusion: Athletes use nutritional and pharmacological aids more to improve performance and gain lean body mass. Mechanical aids were used for recovery and psychological aids for motivation. Self-prescription is common, especially for pharmacological aids.

3.
Int J Exerc Sci ; 16(2): 1025-1037, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37650034

RESUMO

Ischemic preconditioning (IPC) has been an excellent strategy for enhancing sports performance recovery, although there is still no consensus on the ideal protocol. Thus, this study aimed to evaluate the effects of IPC with different cuff pressures (low pressure, medium pressure, and high pressure) on the attenuation of neuromuscular fatigue after an isometric test protocol. And to verify whether this improvement was related to muscle oxygen saturation during the test protocol. Thirty males (18-35 years old) with experience in resistance training were allocated to three different groups: low pressure (20 mmHg), medium pressure (100 mmHg), and high pressure (190 mmHg). The individual occlusion pressure of each participant was identified using ultrasound. Each participant performed two test protocols (8 maximal isometric contractions lasting 20-s with a 10-s rest interval) in an extension chair; after the first test protocol, the participant received the IPC intervention with a low, medium, or high cuff pressure or received the noncuff intervention (randomized order). Only the medium-pressure group showed a smaller decrease in mean force change compared to the no-cuff condition (-4.40% vs. -13.10%, p=0.01, respectively), and the low- and high-pressure groups did not exhibit significant pressure differences (IPC vs. noncuff: -8.40% vs. -13.10%, p=0.11 and -9.10% vs. -14.70%, p=0.12, respectively). Muscle oxygen saturation across test protocols showed no significant differences in all IPC conditions (p>0.05). Although, IPC with medium pressure was effective at optimizing the recovery of neuromuscular performance, this improvement is not related to an increase in muscle oxygen saturation during exercise.

4.
Int J Sports Med ; 44(11): 763-777, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37279792

RESUMO

The development of the rating of perceived exertion (RPE) enables the easy assessment of runners' training strain as well as training load (TL). However, the long-term and retrospective validity of TL assessment using RPE scales still needs further investigation. Therefore, this study examined the validity of weekly and monthly ratings of perceived exertion (W-RPE, M-RPE) in assessing TL in runners. Healthy adult runners (n=53) rated perceived exertion using the modified category-ratio 10 (CR-10) scale for each week of a four-week period, as well as for the month, considering the four-week period. CR-10 for the week and the month were multiplied by the total training time of the week and month, respectively, to assess the W-RPE and M-RPE. Training impulse (TRIMP) was used as the criterion measure. The results indicated that the W-RPE and M-RPE may be used for monitoring TL during prolonged periods, presenting a very large correlations with the criterion measure.


Assuntos
Esforço Físico , Adulto , Humanos , Estudos Retrospectivos , Frequência Cardíaca
5.
Int J Exerc Sci ; 16(4): 217-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113512

RESUMO

We investigated whether acute ischemic preconditioning (IPC) would affect upper limb maximal strength performance in resistance-trained men. Using a counterbalanced randomized crossover design, fifteen men (29.9 ± 5.9 yrs.; 86.3 ± 9.6 kg; 8.0 ± 5.0 yrs. resistance training experience) performed one-repetition maximum (1-RM) bench press tests on three different occasions: control, 10 min post-IPC or 10 min post-placebo (SHAM). One-way analysis of variance showed that the post-IPC condition increased (P < 0.0001) 1-RM loads compared to both control and post-SHAM (control 113.3 ± 15.9 kg vs. SHAM 113.9 ± 15.8 kg vs. IPC 115.7 ± 15.6 kg), while control and SHAM did not differ (P > 0.05). Individual results showed that 13 participants (~87%) improved their performance post-IPC compared to control, and 11 participants (~73%) performed better post-IPC compared to post-SHAM. Reported session rating of perceived exertion (RPE) was lower (P < 0.0001) post-IPC (8.5 ± 0.6 arb.u) compared to control (9.3 ± 0.5 arb.u) and post-SHAM (9.3 ± 0.5 arb.u). Therefore, we conclude that IPC acutely improves upper limb maximal strength performance and reduces session-RPE in resistance-trained men. These results suggest an acute ergogenic effect of IPC for strength and power sports such as powerlifting.

6.
Eur J Appl Physiol ; 123(4): 683-693, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36478078

RESUMO

The findings of the ischemic preconditioning (IPC) on exercise performance are mixed regarding types of exercise, protocols and participants' training status. Additionally, studies comparing IPC with sham (i.e., low-pressure cuff) and/or control (i.e., no cuff) interventions are contentious. While studies comparing IPC versus a control group generally show an IPC significant effect on performance, sham interventions show the same performance improvement. Thus, the controversy over IPC ergogenic effect may be due to limited discussion on the psychophysiological mechanisms underlying cuff maneuvers. Psychophysiology is the study of the interrelationships between mind, body and behavior, and mental processes are the result of the architecture of the nervous system and voluntary exercise is a behavior controlled by the central command modulated by sensory inputs. Therefore, this narrative review aims to associate potential IPC-induced positive effects on performance with sensorimotor pathways (e.g., sham influencing bidirectional body-brain integration), hemodynamic and metabolic changes (i.e., blood flow occlusion reperfusion cycles). Overall, IPC and sham-induced mechanisms on exercise performance may be due to a bidirectional body-brain integration of muscle sensory feedback to the central command resulting in delayed time to exhaustion, alterations on perceptions and behavior. Additionally, hemodynamic responses and higher muscle oxygen extraction may justify the benefits of IPC on muscle contractile function.


Assuntos
Precondicionamento Isquêmico , Humanos , Precondicionamento Isquêmico/métodos , Exercício Físico , Reperfusão , Teste de Esforço , Psicofisiologia , Músculo Esquelético/fisiologia
7.
Transl Sports Med ; 2023: 9507977, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38654909

RESUMO

Trained individuals may require variations in training stimuli and advanced resistance training paradigms (ADV) to increase skeletal muscle hypertrophy. However, no meta-analysis has examined how ADV versus traditional (TRAD) approaches may differentially affect hypertrophic outcomes in trained populations. The aim of this review was to determine whether the skeletal muscle hypertrophy responses induced by TRAD differed from ADV in resistance-trained individuals. Furthermore, we sought to examine potential effects of dietary factors, participants' training status, and training loads. We searched for peer-reviewed, randomized controlled trials (published in English) conducted in healthy resistance-trained adults performing a period of TRAD and ADV with pre-to-post measurement(s) of muscle hypertrophy in PubMed, Web of Science, SPORTDiscus, and MEDLINE databases up to October 2022. A formal meta-analysis was conducted in Revman5, and risk of bias was assessed by ROB2. Ten studies met the inclusion criteria. Results indicated no difference between ADV and TRAD for muscle thickness (SMD = 0.05, 95% CI: -0.20 0.29, p = 0.70), lean mass (SMD = -0.01, 95% CI: -0.26 0.23, p = 0.92), muscle cross-sectional area (SMD = -0.07, 95% CI: -0.36 0.22, p = 0.64), or all measurements analyzed together (SMD = -0.00, 95% CI: -0.15 0.14, p = 0.95). No heterogeneity or inconsistencies were observed; however, unclear risk of bias was present in most of the studies. Short-term ADV does not induce superior skeletal muscle hypertrophy responses when compared with TRAD in trained individuals. This review was not previously registered.

8.
J. Phys. Educ. (Maringá) ; 34: e3437, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528876

RESUMO

ABSTRACT Different competitive environments appears to affect the physical demands during the sports competitions. Thus, the aim of this study was to report the mechanical demand and pacing behaviour of twelve male elite mountain bikers on cross-country short track (XCC) and cross-country Olympic (XCO). During both competition, total race time, speed, power output (PO) and cadence (CA) were recorded. As the race time in the XCC is shorter (21.0 ± 0.5 vs 84.0 ± 3.0 min; p<0.01), the average speed (26.6 ± 0.6 vs 17.8 ± 0.6 km/h; p<0.01), PO (365.0 ± 26.7 vs 301.0 ± 26.2 watts; p<0.01) and CA (81.2 ± 4.7 vs 77.4 ± 4.3 rev∙min−1; p=0.01) were higher than the XCO. While a variable pacing was adopted during XCC, a positive profile was adopted in XCO. In addition, athletes adopted a more conservative starting pace during XCC (below average race speed) but a faster start during XCO (above average race speed). These findings demonstrated that mechanical parameters and pacing profile adopted by cyclists are different between XCC and XCO. Therefore, mountain bikers and coaches must develop specific strategy and training methods in order to obtain success in each competition.


RESUMO Diferentes ambientes competitivos parecem afetar as demandas físicas durante as competições esportivas. Assim, o objetivo deste estudo foi reportar as demandas mecânicas e o comportamento do pacing de doze homens ciclistas de montanha da categoria elite durante o cross-country de pista curta (XCC) e o cross-country Olímpico (XCO). Durante ambas as competições, o tempo total de corrida, velocidade, potência (PO) e cadência (CA) foram gravados. Como o tempo de prova do XCC é menor (21,0±0,5 vs 84,0±3,0 min; p<0,01), a velocidade média (26,6±0,6 vs 17,8±0,6 km/h; p<0,01), PO (365,0±26,7 vs 301,0±26,2 watts; p<0,01) e CA (81,2±4,7 vs 77,4±4,3 rev∙min−1; p=0,01) foram maiores que no XCO. Enquanto um ritmo variável foi adotado no XCC, um perfil positivo foi adotado no XCO. Além disso, os atletas adotaram um ritmo inicial mais conservador durante o XCC (abaixo da velocidade média da prova), mas um início mais rápido durante o XCO (velocidade acima da média da prova). Esses achados demonstraram que os parâmetros mecânicos e o ritmo adotados pelos ciclistas são diferentes entre o XCC e XCO. Portanto, ciclistas e treinadores devem desenvolver estratégias e métodos de treinamento específicos para obter sucesso em cada competição.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36231848

RESUMO

Mountain biking (MTB) is a cycling modality performed on a variety of unpaved terrain. Although the cross-country Olympic race is the most popular cross-country (XC) format, other XC events have gained increased attention. XC-MTB has repeatedly modified its rules and race format. Moreover, bikes have been modified throughout the years in order to improve riding performance. Therefore, the aim of this review was to present the most relevant studies and discuss the main results on the XC-MTB. Limited evidence on the topic suggests that the XC-MTB events present a variation in exercise intensity, demanding cardiovascular fitness and high power output. Nonetheless, these responses and demands seem to change according to each event. The characteristics of the cyclists differ according to the performance level, suggesting that these parameters may be important to achieve superior performance in XC-MTB. Moreover, factors such as pacing and ability to perform technical sections of the circuit might influence general performance. Bicycles equipped with front and rear suspension (i.e., full suspension) and 29″ wheels have been shown to be effective on the XC circuit. Lastly, strategies such as protective equipment, bike fit, resistance training and accident prevention measures can reduce the severity and the number of injuries.


Assuntos
Ciclismo , Esportes , Prevenção de Acidentes , Acidentes , Ciclismo/fisiologia , Exercício Físico
11.
Sports (Basel) ; 10(8)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36006086

RESUMO

The present study investigated whether acute capsaicin (CAP) supplementation improves mean power output (MPO) and peak velocity (PV) during the performance of the free bench press exercise (FBP). Twelve (n = 12) male Brazilian Jiu-Jitsu (BJJ) athletes (age: 24.3 ± 1.5 years, height: 1.74 ± 0.1 m, body mass: 75.7 ± 10.1 kg) participated in this randomized, placebo (PLA)-controlled, double-blind, crossover trial. For each condition, 45 min after CAP (12 mg purified) or PLA (12 mg of Celulomax E) consumption, the participants performed four sets of five repetitions of FBP at a load of 60% of body mass with five-min rest intervals. The MPO (t = 5.6, df = 11, p = 0.001, EF = 0.3, IC 95% = -0.55 to 1.05) and PV (t = 5.4, df = 11, p = 0.001, EF = 0.5, IC 95% = -0.32 to 1.30) were significantly higher with CAP supplementation versus PLA. Acute CAP supplementation appears to improve MPO and PV during FBP in male BJJ athletes.

14.
Artigo em Inglês | MEDLINE | ID: mdl-35270564

RESUMO

Background: Chronic diseases are the leading causes of death and disability in older women. Physical exercise training programs promote beneficial effects for health and quality of life. However, exercise interruption periods may be detrimental for the hemodynamic and lipidic profiles of hypertensive older women with dyslipidemia. Methods: Nineteen hypertensive older women with dyslipidemia (exercise group: 67.5 ± 5.4 years, 1.53 ± 3.42 m, 71.84 ± 7.45 kg) performed a supervised multicomponent exercise training program (METP) during nine months, followed by a one-year detraining period (DT), while fourteen hypertensive older women (control group: 66.4 ± 5.2 years, 1.56 ± 3.10 m, 69.38 ± 5.24 kg) with dyslipidemia kept their continued daily routine without exercise. For both groups, hemodynamic and lipidic profiles and functional capacities (FCs) were assessed four times: before and after the METP and after 3 and 12 months of DT (no exercise was carried out). Results: The METP improved hemodynamic and lipidic profiles (p < 0.05), while three months of DT decreased all (p < 0.05) parameters, with the exception of diastolic blood pressure (DBP). One year of DT significantly (p < 0.01) decreased systolic blood pressure (7.85%), DBP (2.29%), resting heart rate (7.95%), blood glucose (19.14%), total cholesterol (10.27%), triglycerides (6.92%) and FC­agility (4.24%), lower- (−12.75%) and upper-body strength (−12.17%), cardiorespiratory capacity (−4.81%) and lower- (−16.16%) and upper-body flexibility (−11.11%). Conclusion: Nine months of the exercise program significantly improved the hemodynamic and lipid profiles as well as the functional capacities of hypertensive older women with dyslipidemia. Although a detraining period is detrimental to these benefits, it seems that the first three months are more prominent in these alterations.


Assuntos
Hipertensão , Qualidade de Vida , Idoso , Pressão Sanguínea , Exercício Físico/fisiologia , Terapia por Exercício , Feminino , Humanos , Hipertensão/terapia
15.
Sports Med Int Open ; 6(1): E1-E8, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35211651

RESUMO

We analyzed the effects of wearing blue lenses on melatonin level, physical and cognitive performance. Fifteen youth volleyball players (15.0±1.5 yrs) attended the laboratory on 3 occasions (48-h interval): on the 1 st visit they were familiarized with the procedures of the study, and on 2 nd and 3 rd visits they were submitted to the testing protocol wearing transparent (control) or blue lens glasses in a counterbalanced crossover design. The protocol consisted of 10 min in "total darkness," 30 min of light stimulation (wearing blue or transparent lenses), followed by an attentional test, and an agility T-test (without wearing the glasses). Samples of saliva (to determine melatonin concentration) were obtained pre- and post-exposure (30 min) to artificial light, wearing the lenses. Sleepiness, alertness, attention, mood, and perceived recovery status and performance variables (reaction time and T-test) were assessed after lens exposure. Melatonin levels did not differ within and between groups (blue lenses, pre: 0.79±0.73 and post: 1.19±1.374 pg/dl, p=0.252, effect size (ES)=0.38; control, pre: 0.97±1.00 and post: 0.67±0.71 pg/dl, p=0.305, ES=-0.35). Nonetheless, melatonin differences were significantly correlated with physical sedation for glasses with blue lenses (r=-0.526; p=0.04). No other variables differed (p>0.05) between protocols, including T-test performance (p=0.07; ES=0.41). Blue lenses do not influence melatonin levels, cognitive/physical performance, and mood status in amateur youth volleyball players.

17.
Motriz (Online) ; 28: e10220004122, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406009

RESUMO

Abstract Aim: To verify the response of tissue saturation index (TSI) during ischemia-reperfusion (IR) interventions with different cuff-pressures. Methods: Twenty-nine healthy men experienced in resistance training were recruited. Each one has undergone a control condition (no cuff) and one of the three IR interventions: 1) 190 mmHg (CP-190, 22.7 ± 3.0 years; 176.6 ± 3.9 cm; 77.3 ± 9.5 kg; 2) 100 mmHg (CP-100, 22.9 ± 6.3 years; 180.5 ± 4.0 cm; 85.2 ± 14.1 kg) and 3) 20 mmHg (CP-20, 20.3 ± 2.4 years; 171.8 ± 5.2 cm; 72.4 ± 6.0 kg). Cuffs were placed on the proximal region of the thighs. IR interventions consisted of three cycles of 2-min occlusion-reperfusion. TSI was measured using near-infrared spectroscopy (NIRS), positioned on the middle portion of the vastus lateralis of the dominant leg. The oxygenation was measured at the control conditions (no cuff) and during cuff interventions. Results: While TSI values of CP-20 did not change compared to control (p > 0.05), the TSI in CP-190 was lower in the ischemia (p < 0.05), and CP-100 was lower in the second and third ischemia (p < 0.05). However, the TSI value increased during reperfusion but did not return to control levels (p < 0.05). Conclusion: TSI of the CP-190 significantly decreased during ischemia. However, these values increased by about 16% in the reperfusion period. Thus, our results show that the RI intervention may have caused an increase in metabolic demand, as even with the release of blood flow, the TSI values were below those of the other interventions.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34831671

RESUMO

Instagram (IG) reaches millions of people, sharing personal content and all kinds of information, including those related to exercise and health. However, the scientific quality of the posted information is questionable. Thus, this study aimed to analyze whether exercise and health information posted by popular Brazilian IG influencers has technical-scientific accuracy. A personal IG account was created to identify Brazilian IG profiles. The inclusion criteria of the accounts were: (1) having 50% of all the shared posts related to topics about exercise and health, such as nutrition, health and wellness, medicine, or physical fitness; and (2) having over 100,000 followers. Qualitative analysis revealed a low quality percentage (38.79 ± 25.43%) for all analyzed posts. Out of all the posts, only 13 (~2.7%) cited a reference endorsing the information. Moreover, the higher quality-ratio score of the posts was not directly associated with the higher educational qualification of the influencers (r = 0.313; p = 0.076). Nevertheless, the number of followers was inversely correlated with the educational qualification of the influencers (r = -0.450; p = 0.009), but not with the quality-ratio score of the posts (r = -0.178 p = 0.322). We conclude that prominent Brazilian IG influencers disseminate low-quality information about exercise and health, contributing to the wide-spreading of misinformation to millions of followers.


Assuntos
Mídias Sociais , Brasil , Comunicação , Exercício Físico , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-34682474

RESUMO

BACKGROUND: Physical inactivity is a primary cause of most chronic diseases. In addition, the negative effects of aging, physical inactivity and dyslipidemia are risk factors for cardiovascular diseases of older women. Exercise is considered fundamental for the treatment and prevention due to the benefits in the health of this population, but detraining periods after exercise can reverse them. Multicomponent exercise (ME) is a combined method of aerobic and resistance training that can improve the lipidic profile of older women with high cholesterol and triglycerides. METHODS: Seventeen older women (EG: 65.3 ± 4.7 years, 1.52 ± 4.12 m) followed a supervised ME program of nine months and three months of detraining (DT), and fifteen older women (CG: 66.4 ± 5.2 years, 1.54 ± 5.58 cm) continued their daily routine, without exercise. Total cholesterol (TC), triglycerides (TG), blood glucose (GL) and functional capacity (FC) were evaluated at the beginning and at the end of the program and after three months of DT. RESULTS: ME program improved (p < 0.05) lipidic profile: GL (-15.6%), TC (-15.3%), TG (-19.3%) and FC: agility (-13.3%), lower body strength (27.78%), upper body strength (26.3%), cardiorespiratory capacity (11.2%), lower body flexibility (66.67%) and upper body flexibility (85.72%). DT declined the lipidic profile and FC (p < 0.05). CONCLUSION: Lipidic profile and functional capacity can be improved with nine months of ME. Besides the negative effects of DT, three months were not enough to reverse the benefits of exercise in older women with high values of TG and TC.


Assuntos
Exercício Físico , Treinamento de Força , Idoso , Colesterol , Terapia por Exercício , Feminino , Humanos , Triglicerídeos
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