A resistência do fluxo inspiratório modifica a intensidade de uma sessão de pilates? / Does inspiratory flow resistance modify the intensity of a pilates session?

INTRODUÇÃO: As evidências sobre a melhora da capacidade funcional utilizando o Método Pilates não são contundentes. Uma possibilidade de melhorar o efeito de uma sessão de Pilates sobre a capacidade cardiorrespiratória de seus praticantes é utilizar a resistência de fluxo inspiratório (RFI) de forma concomitante. Esse efeito pode ser visualizado através da determinação do limiar glicêmico (LG), técnica utilizada como marcador de intensidade do exercício. OBJETIVO: Testar a hipótese de que a utilização de RFI em uma sessão de pilates antecipa o LG. MÉTODOS: Estudo crossover de corte transversal. Foram avaliados 26 indivíduos de ambos os sexos, sendo 10 do sexo masculino, sadios e com idade entre 20 e 40 anos. Os voluntários foram randomizados para dois protocolos: Protocolo RFI ­ 11 movimentos do Método Pilates com RFI utilizando 20% da pressão inspiratória máxima; e Protocolo sem RFI (SRFI) ­ 11 movimentos do Método Pilates sem RFI. Os dois protocolos foram realizados no mesmo dia, sendo um pela manhã e outro à tarde, conforme randomização feita por sorteio aleatório simples. No repouso e ao final de cada movimento coletas de sangue capilar foram realizadas para dosagem da glicemia e construção da curva glicêmica. O LG foi determinado no menor ponto da curva. RESULTADOS: O LG foi antecipado no protocolo que utilizou RFI, ou seja, no protocolo com RFI o LG foi visualizado no sexto exercício, enquanto no protocolo SRFI o LG foi visualizado no nono exercício (p<0,05). CONCLUSÃO: A RFI antecipou o LG, o que sugere que a RFI aumenta a intensidade de uma sessão de pilates. Isso aventa a hipótese de que a RFI pode proporcionar a médio e longo prazo benefícios adicionais aos praticantes do Método Pilates.

INTRODUCTION: The evidence on the improvement of functional capacity using the Pilates Method is not conclusive. One possibility to improve the effect of a Pilates session on the cardiorespiratory capacity of its practitioners is to use the inspiratory flow resistance (IFR) concomitantly. This effect can be visualized by determining the glycemic threshold (GT), a technique used as an exercise intensity marker. OBJECTIVE: To test the hypothesis that the use of IFR in a Pilates session anticipates GT. METHODS: Cross-sectional crossover study. A total of 26 individuals of both genders were evaluated, 10 of whom were male, healthy, and aged between 20 and 40 years. The volunteers were randomized to two protocols: Protocol IFR - Eleven movements of the Pilates method with IFR using 20% of the maximum inspiratory pressure, and Protocol no IFR (NIFR) - Eleven movements of the Pilates method without IFR. The two protocols were performed on the same day, one in the morning and the other in the afternoon, according to randomization by simple random draw. At rest and at the end of each movement, capillary blood collections were performed to measure blood glucose and construct the glycemic curve. GT was determined at the smallest point on the curve. RESULTS: The GT was anticipated in the protocol that used IFR; that is, in the protocol with IFR, the GT was visualized in the sixth exercise, while in the NIFR protocol, the GT was visualized in the ninth exercise (p<0.05). CONCLUSION: IFR anticipated GT, which suggests that IFR increases the intensity of a Pilates session. This suggests the hypothesis that IFR can provide additional medium and long-term benefits to Pilates method practitioners.

L-menthol administration facilitates breathing comfort during exhaustive endurance running and improves running capacity in well-trained runners: A randomized crossover study.

ABSTRACTThis study aimed to clarify the contribution of L-menthol administration to endurande exercise capacity. Thirteen male runners (age, 35.8 ± 7.8 years; peak oxygen uptake, 62.7 ± 6.8 mL kg-1 min-1) ran on treadmills at fixed intensities of their anaerobic thresholds to exhaustion. All participants underwent three trials-water ingestion (W-IG), L-menthol mouth rinsing (M-MR), and L-menthol ingestion (M-IG)- in a random order every 5 min while running. Breathing comfort (BC) was measured immediately after fluid intake. Dyspnea threshold against external inspiratory resistance was examined before and after the running test. The running time with M-IG (1683.9 ± 520.3 s) was longer than that with W-IG (1410.2 ± 465.9 s, effect size [ES] = 0.55). BC with M-IG (2.00 ± 0.74) was higher than that with W-IG (0.42 ± 0.79) at exhaustion (ES > 2.00). The dyspnea threshold after running decreased to 19.2 ± 7.6 cm H2O L-1 s-1 with W-IG, whereas that with M-MR (26.2 ± 6.5 cm H2O L-1 s-1) and M-IG (29.2 ± 2.8 cm H2O L-1 s-1) remained high (p for interaction < 0.001). M-IG facilitated BC during running, improved endurance capacity, and prevented decreases in the dyspnea threshold against external inspiratory resistance after exhaustive running.HighlightsL-menthol ingestion facilitated breathing comfort during high intensity endurance running and improved exhaustive endurance running capacity.Even after exhaustion, L-menthol solution relieved dyspnea sensitivity against external inspiratory resistance.L-menthol ingestion might help athletes improve their endurance running capacity.

Attentive Processes and Blood Lactate in the Sambo.

BACKGROUND: Sambo is a martial art and combat sport that originated in the Soviet Union. There are two main stiles, Sport Sambo and Combat Sambo which resembles modern mixed martial arts. Very little literature is available about physiological aspects of Sambo and, in particular, on the possible effects on cognitive domains. The purpose of the present research was to determine if there is a correlation between a blood lactate increase and the intensity and/or selectivity of attentions. METHODS: Sixteen male athletes practicing Sambo for at least 5 years participated voluntarily in the study. Each athlete had to sustain, with an interval of one week, both a Sport Sambo match and a Combat Sambo match, each lasting 5 min. Blood lactate levels as well as attentive capacities were evaluated at three different times: at rest, i.e., 5 min before the start of the session (pre), at end of the session and 15 min after its conclusion. Reaction time protocol was used to evaluate the intensity of attention, whereas divided attention was assessed for analyzing the selectivity of attention together with errors and omissions. RESULTS: Concerning Sport Sambo, blood lactate was 1.66 mmol/L (±0.55 SD) before the session, reached a mean value of 3.40 mmol/L (±0.45 SD) at the end of the session (end) and returned to values similar to initial ones (a mean value of 1.98 mmol/L (±0.37 SD) after 15 min (15-end). None of the attentive parameters examined, showed statistically significant differences. Conversely, for Combat Sambo, it was found a significant increase in blood lactate levels that went from 1.66 mmol/L (±0.55 SD) before the session (pre), to 4.76 mmol/L (±0.60 SD) at the end (end) and then back to values similar to those observed before the session 15 min after its conclusion (15-end), i.e., 1.97 mmol/L (±0.37 SD); however, after a Combat Sambo session increases in blood lactate were associated with significant worsening of attentional mechanisms. CONCLUSIONS: In conclusion, in all the participants, the worsening of attentional mechanisms was observed only after the Combat Sambo session in which blood lactate values exceeded 4 mmol/L. This figure, also known as the Onset of Blood Lactate Accumulation (OBLA), is commonly used to determine the anaerobic threshold.

[The characteristics of core parameters during cardiopulmonary exercise testing in patients with hypertrophy cardiomyopathy].

Objective: The patients with Hypertrophic CardioMyopathy (HCM), characterized by hypertrophy of the myocardium with a high risk of sudden death, was less clear for the exercise pathophysiology. Under the guidance of holistic integrative physiology and medicine (HIPM), the ramp protocol symptom-limited CardioPulmonary Exercise Testing (CPET) is the only method to evaluate the overall functional status of human body. We investigated the CPET pathophysiology in patients with HCM. Methods: From April 2017 to January 2020, 244 subjects were enrolled after signed the informed consent form and completing CPET in Fuwai Hospital. They 219 HCM patients and 25 healthy normal subjects as control (NS). The changes of CPET core parameters between two them were calculated, compared and did Individual analysis. Results: ①The gender of HCM was 163 maleand 56 female. The gender of NS was 11 male and 14 female. The age of HCM was (46.7±12.8, 16.0~71.0) year; NS was (43.7±10.4, 26.0~61.0) year.②The core CPET parameters of HCM: peak oxygen uptake (Peak VO2) was (65.2±13.8, 22.8~103.4) %pred; anaerobic threshold (AT) was (66.4±13.0, 33.7~103.5) %pred; Peak O2 pulse was (84.3±19.0, 90.9~126.0)%pred; oxygen uptake efficiency platform (OUEP) was (99.2±13.4, 69.1~155.5) %pred; Lowest VE/VCO2 was (108.0±13.2, 70.4~154.0)%pred; VE/VCO2 Slope was (108.5±17.9, 66.9~164.9)%pred. Compared with NS, the Peak VO2, AT, Peak O2 pulse, and OUEP were significantly decreased (P<0.01 or P<0.05), but the Lowest VE/VCO2 and VE/VCO2 Slope were significantly increased (P<0.05). For Individual analysis of the overall functional status of CPET, some were very sever but some HCM were still within the normal range.③ The Peak VO2 was positively correlated with AT, OUEP, Peak O2 pulse, and peak systolic blood pressure, but was negative correlated with Lowest VE/VCO2 and VE/VCO2 Slope. Conclusion: CPET is safe and specific characteristics for patients with HCM, which deserve further research and clinical application. Under HIPM guidance, CPET can not only be used for overall functional evaluation, disease diagnosis and differential diagnosis, risk stratification, curative effect evaluation and accurate prognostic prediction, but also be utilized in formulating the individualized training prescription and management of chronic diseases.

[Clinical study on the characteristics of exercise pathophysiological in patients with severe heart failure].

Objective: The cardiopulmonary function of patients with chronic heart failure (CHF) was severely limited, but the holistic integrative exercise pathophysiology is still unclear. Methods: After signed the consent form, Eighty three patients with severe CHF from October 2016 to October 2017 in Fuwai Hospital were performed Ramp incremental loading program CardioPulmonary Exercise Testing (CPET), and 12 normal subjects served as control. CPET were performed according to standard of Harbor-UCLA MC and the circulatory, respiratory and metabolic parameters during CPET were measured and analyzed. Results: Peak oxygen uptake (Peak VO2) in CHF (14.33±2.69) ml/(min·kg), (44.25±14.74)%pred was significantly lower than control ((29.42±5.46) ml/(min·kg), (83.88±6.28)%pred). Other core parameters of CPET such as anaerobic threshold (AT), peak oxygen pulse, oxygen uptake efficiency platform (OUEP), the lowest of carbon dioxide output ventilation ratio (Lowest VE/VCO2), and carbon dioxide output ventilation slope (VE/VCO2 Slope) in CHF were significantly different with the control group(P<0.01). The core parameters of lung function, such as forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, and carbon monoxide diffusion (DLCO) were significantly decreased (P<0.01). Systolic blood pressure during all stages of CPET in CHF was significantly lower than control group (P<0.05); Heart rate at AT, peak and recovery stages were significantly lower than control (P<0.01). Minute ventilation, tidal volume and respiratory frequency at rest, warm-up were significantly higher than control (P<0.05). Tidal volume at recovery was significantly higher than control (P<0.05). VO2 at AT, peak and recovery stages in CHF were significantly higher than control (P<0.01). Oxygen pulse at AT and peak were significantly higher than control (P<0.01). Pulse oxygen saturation during all stages of CPET in CHF were significantly lower than control (P<0.01). Conclusion: The decreased holistic functional capacity of cardiogenic CHF dominantly due to circulatory limitation, and secondly due to respiratory and metabolic limitation.

[Cardiopulmonary exercise testing was used to evaluate objectively and quantitatively the holistic function in patients after neoadjuvant chemotherapy].

Objective: Cardiopulmonary exercise testing(CPET)was used to evaluate objectively and quantitatively the holistic function in patients accepted preoperative chemotherapy. Methods: This study investigated reliable objective and quantitative assessment methods of symptom limited maximal incremental CPET before and after chemotherapy in patients with 6 esophageal cancer. We re-analyzed the changes in cardiopulmonary, metabolism, and other functions physiologic parameters of CPET. Results: After patients accepted preoperative chemotherapy,Peak oxygen consumption (Peak VO2)(P<0.05), anaerobic threshold (AT) and peak oxygen pulse (Peak O2 paulse), oxygen uptake efficiency plateau (OUEP)were decreased (P<0.01). The lowest of ventilatory equivalent for carbon dioxide and slope of ventilatory equivalent for carbon dioxide were increased (P<0.05). For individual of all patients, except one patient's Peak VO2 and OUEP slightly increased,all of the above indicators were reduced in the remaining patients. The lowest of ventilatory equivalent for carbon dioxide and slope of ventilatory equivalent for carbon dioxide increased in all the patients,except one patient's slope of ventilatory equivalent for carbon dioxide decreased slightly. The heart rate of 6 patients showed an upward trend in each state, but there was no statistical difference. Three of the 6 patients had blood pressure measurement, and the other 3 patients had a significant decrease in diastolic blood pressure (P<0.05) except at extreme state.The patients had lower oxygen uptake at AT(P<0. 01) and extreme state (P<0. 05) than that before chemotherapy. The oxygen uptake efficiency in a warm-up state(P<0. 01),and an AT state(P<0. 05)after chemotherapy were lower than those before chemotherapy. The ventilator equivalent for carbon dioxide after chemotherapy was in the each states presented an upward trend, but only ventilator equivalent for carbon dioxide after in the warm-up state (P<0.05) and AT(P<0.01) had statistical significance. oxygen pulse in all four states showed a decreasing trend, and only at AT (P<0.05) showed a significant decrease.After chemotherapy,the PETCO2 in a warm-up state after chemotherapy was lower than that before chemotherapy(P<0. 05); the PETO2 in a quiescent state,a warm - up state,and an extreme state after chemotherapy were higher than those before chemotherapy;but there was nosignificant difference. Conclusion: The holistic functional capacity of patients with esophageal significantly decreased after 136 days chemotherapy. The circulatory functionalandentilator functional parameters significantly decreased after chemotherapy.

Maximal and Submaximal Cardiorespiratory Responses to a Novel Graded Karate Test.

The present study aimed to propose and assess the physiological responses of a novel graded karate test. Ten male national-level karate athletes (age 26 ± 5 yrs; body mass 69.5 ± 11.6 kg; height 1.70 ± 0.09 m) performed two exercise tests (separated by 2-7 days): 1) a running-based cardiopulmonary exercise test; 2) a graded karate test. The cardiopulmonary exercise test was comprised of an individualized ramp protocol for treadmill running, and the graded karate test was comprised of a sequence of 'kisami-gyaku-zuki" punching at a fixed frequency of a stationary target that becomes progressively distant. Cardiorespiratory responses, blood lactate concentration, and perceived exertion were measured. A verification phase was also performed in both tests to confirm the maximal physiological outcomes. The graded karate test evoked similar maximal responses to the running protocol: V̇O2 (57.4 ± 5.1 vs 58.3 ± 3.5 mL·kg-1·min-1; p = 0.53), heart rate (192 ± 6 vs 193 ± 10]beats.min-1; p = 0.62) and blood lactate (14.6 ± 3.4 vs 13.1 ± 3.0 mmol·L-1; p = 0.14) with a shorter duration (351 ± 71 vs 640 ± 9 s; p < 0.001). Additionally, the graded karate test evoked higher V̇O2 (72.6 ± 6.5 vs 64.4 ± 4.3 %V̇O2MAX; p = 0.005) and heart rate (89.4 ± 4.6 vs 77.3 ± 7.2 %HRMAX p < 0.001) at the ventilatory threshold and a higher heart rate (97.0 ± 2.4 vs 92.9 ± 2.2 %HRMAX; p = 0.02) at the respiratory compensation point. Incremental and verification phases evoked similar responses in V̇O2 and minute-ventilation during both tests. This novel displacement-based sport-specific test evoked similar maximal and higher submaximal responses, indicating a superior pathway to assess karate athletes.

Aerobic training associated with an active lifestyle exerts a protective effect against oxidative damage in hypothalamus and liver: The involvement of energy metabolism.

BACKGROUND: Oxidation resistance protein 1 (OXR1) is of scientific interest due its role in protecting tissues against oxidative stress, DNA mutations and tumorigenesis, but little is known regarding strategies to increase OXR1 in different tissues. As an improved antioxidant defense may result from a high total amount of physical activity, the present study was designed to determine whether an active lifestyle including aerobic training exercise and spontaneous physical activity (SPA) can increase OXR1. We have built a large cage (LC) that allows animals to move freely, promoting an increase in SPA in comparison to a small cage (SC). METHODS: We examined the effects of aerobic training applied for 8 weeks on SPA and OXR1 of C57BL/6 J mice living in two types of housing (SC and LC). OXR1 protein was studied in hypothalamus, muscle and liver, which were chosen due to their important role in energy and metabolic homeostasis. RESULTS: LC-mice were more active than SC-mice as determined by SPA values. Despite both trained groups exhibiting similar gains in aerobic capacity, only trained mice kept in a large cage (but not for trained mice housed in SC) exhibited high OXR1 in the hypothalamus and liver. Trained mice housed in LC that exhibited an up-regulation of OXR1 also were those who exhibited an energy-expensive metabolism (based on metabolic parameters). CONCLUSIONS: These results suggest that aerobic training associated with a more active lifestyle exerts a protective effect against oxidative damage and may be induced by changes in energy metabolism.

Inspiratory Muscle Training Improves Aerobic Capacity in Amateur Indoor Football Players.

Inspiratory muscle training represents a recommended clinical practice to improve physical performance of healthy individuals, athletes, and those with chronic diseases. This study aimed to evaluate whether high- and low-intensity inspiratory muscle training interferes with the aerobic capacity of indoor soccer players. Volunteers were equally and randomly divided into CON (control group, no inspiratory muscle training); HIG (high-intensity group, inspiratory muscle training at 80% of maximal inspiratory pressure, 3 sets of 12 repetitions); and LIG (low-intensity group, inspiratory muscle training at 50% of maximal inspiratory pressure, 2 sets of 20 repetitions). Before and after inspiratory muscle training, maximal inspiratory and expiratory pressures, the incremental shuttle run test, and the 3-min step test were evaluated. Both inspiratory muscle training protocols improved maximal inspiratory and expiratory pressures, and indirect maximal oxygen consumption and distance traveled in the shuttle test compared to CON. However, only HIG achieved significant increases of indirect oxygen consumption and frequency of step rise in the 3-min step test (p<0.05). Inspiratory muscle training is an important tool to enhance maximal inspiratory pressure and exercise tolerance with potential benefits on submaximal aerobic capacity. However, high-intensity inspiratory muscle training improved aerobic capacity in amateur indoor soccer players in both submaximal tests.

Inspiratory muscle training based on anaerobic threshold on the functional capacity of patients after coronary artery bypass grafting: clinical trial

Abstract Introduction: Coronary artery bypass grafting (CABG) is associated with reduced ventilatory muscle strength and consequent worsening of functional capacity (FC). Inspiratory Muscle Training (IMT) can be indicated, but there is still a lack of knowledge about the use of the anaerobic threshold (AT) as a basis for prescription. The objective of this study is to evaluate if IMT based on AT modifies FC and inspiratory muscle strength of patients submitted to CABG. Methods: This is a clinical trial. On the first postoperative day, the patients were divided into two groups: the conventional group (IMT-C), which performed IMT based on 40% of maximal inspiratory pressure (MIP), and the IMT-AT group, which performed IMT based on AT. All patients underwent preoperative and postoperative assessment of MIP and performed a six-minute walk test (6MWT). Results: Forty-two patients were evaluated, 21 in each group. Their mean age was 61.4±10 years and 27 (64%) of them were male. There was a reduction of inspiratory muscle strength with a delta of 23±13 cmH2O in the IMT-C group vs. 11±10 cmH2O in the IMT-AT group (P<0.01) and of the walking distance with a delta of 94±34 meters in the IMT-C group vs. 57±30 meters in the IMT-AT group (P=0.04). Conclusion: IMT based on AT minimized the loss of FC and inspiratory muscle strength of patients submitted to CABG.

Inspiratory Muscle Training Based on Anaerobic Threshold on the Functional Capacity of Patients After Coronary Artery Bypass Grafting: Clinical Trial.

INTRODUCTION: Coronary artery bypass grafting (CABG) is associated with reduced ventilatory muscle strength and consequent worsening of functional capacity (FC). Inspiratory Muscle Training (IMT) can be indicated, but there is still a lack of knowledge about the use of the anaerobic threshold (AT) as a basis for prescription. The objective of this study is to evaluate if IMT based on AT modifies FC and inspiratory muscle strength of patients submitted to CABG. METHODS: This is a clinical trial. On the first postoperative day, the patients were divided into two groups: the conventional group (IMT-C), which performed IMT based on 40% of maximal inspiratory pressure (MIP), and the IMT-AT group, which performed IMT based on AT. All patients underwent preoperative and postoperative assessment of MIP and performed a six-minute walk test (6MWT). RESULTS: Forty-two patients were evaluated, 21 in each group. Their mean age was 61.4±10 years and 27 (64%) of them were male. There was a reduction of inspiratory muscle strength with a delta of 23±13 cmH2O in the IMT-C group vs. 11±10 cmH2O in the IMT-AT group (P<0.01) and of the walking distance with a delta of 94±34 meters in the IMT-C group vs. 57±30 meters in the IMT-AT group (P=0.04). CONCLUSION: IMT based on AT minimized the loss of FC and inspiratory muscle strength of patients submitted to CABG.

Re-esterified DHA improves ventilatory threshold 2 in competitive amateur cyclists.

BACKGROUND: Fish oils were studied as ergogenic aids in a number of mixed physical trial designs showing promising results. However, the heterogeneous purity of the studied supplements, combined with the variety of physical tests employed call for more studies to confirm these findings, ideally with standardised supplements. Our aim was to test a supplement highly concentrated in DHA (DHA:EPA ratio equal to approximately 8:1) on a maximal cycling test to elucidate performance improvements mainly due to DHA. METHODS: A double-blind, placebo controlled, randomised balanced, parallel design, in competitive amateur cyclists was employed. They were all male, older than 18 years old, with training routine of 2 to 4 sessions per week lasting at least one hour each. A ramp cycling test to exhaustion with a subsequent 5 min recovery phase was employed before and after treatment to analyse aerobic metabolism and lactate clearance after the bout. After 30 days of supplementation with 975 mg of re-esterified DHA, the thirty-eight cyclist who completed the study were finally included for statistical analysis. RESULTS: Mean power output at ventilatory threshold 2 (VT2) improved after DHA supplementation both as absolute (△DHA versus △PLA: 6.33-26.54 Watts; CI 95%) and relative (p=0.006) values, paralleled with higher oxygen consumption at VT2 both for absolute (DHA 2729.4 ±304.5, 3045.9 ±335.0; PLA 2792.3 ±339.5, 2845.5 ±357.1; ml·min-1 baseline versus post p=0.025) and relative values (DHA 36.6 ±5.0, 41.2 ±5.4; PLA 37.2 ±5.7, 38.1 ±5.2; ml·kg-1·min-1 baseline versus post p=0.024). Heart rate recovery rate improved during the recovery phase in the DHA group compared to PLA (p=0.005). CONCLUSION: DHA is capable of improving mean power output at the ventilatory threshold 2 (anaerobic ventilatory threshold) in amateur competitive cyclists. It is unclear if these findings are the result of the specific DHA supplement blend or another factor.

The gender dependent influence of sodium bicarbonate supplementation on anaerobic power and specific performance in female and male wrestlers.

The aim of this study was the assessment of progressive low-dose sodium bicarbonate (NaHCO3) supplementation on the anaerobic indices in two bouts of Wingate tests (WT) separated by wrestling-specific performance test and assessing the gender differences in response. Fifty-one (18 F) wrestlers completed a randomized trial of either a NaHCO3 (up to 100 mg·kg-1) or a placebo for 10 days. Before and after treatment, athletes completed an exercise protocol that comprised, in sequence, the first WT1, dummy throw test (DT), and second WT2. The number of completed throws increased significantly in males from 19.3 ± 2.6 NaHCO3pre to 21.7 ± 2.9 NaHCO3post. ΔWT2-WT1 improved particularly in the midsection of 30-s WT on NaHCO3. However, no significant differences were found in peak power (PP), power drop (PD) and average power (AP) (analyzed separately for each WT), and ΔWT2-WT1 in PP and PD. Interaction with gender was significant for AP, PP and PD, every second of WT1 and WT2, as well as DT test. In conclusion, our study suggests that the response to NaHCO3 may be gender-specific and progressive low-dose NaHCO3 supplementation allows the advantageous strengthening of wrestling-specific performance in males. It can also lead to maintenance of high anaerobic power mainly in the midsection of the 30-s Wingate test.

Acute fatigue affects reaction times and reaction consistency in Mixed Martial Arts fighters.

Mixed Martial Arts (MMA) is a multielement combat sport where fighters need to quickly react to an opponent's movements under fatigued conditions. Research indicates that fast reaction time is important in many sports, but the effect of fatigue has shown negative, null, or even positive influences on reaction time. However, few studies have been conducted in a controlled setting, especially using MMA figthers, whose matches are frequently resolved in a split-second. Therefore, this study investigated whether acute neuromuscular fatigue affects reaction and movement times, and their consistency in MMA fighters (N = 45). Before and after an upper-body Wingate test, a simple visual reaction time task was completed. Results showed a significant negative effect of fatigue on the reaction times and their consistency, with longer reactions (1.5% change) and lower consistency (14.7% change) after the Wingate test. Further, greater amounts of fatigue during the Wingate test seemed to negatively affect the consistency of post-Wingate movement time. Due to cumulative fatigue and the dynamic nature of MMA, our data indicate that not only the decrements in aerobic and anaerobic power likely affect a fighter's performance, but their reaction time and motor time may also be compromised during a fight.

Effect of Ten Weeks of Creatine Monohydrate Plus HMB Supplementation on Athletic Performance Tests in Elite Male Endurance Athletes.

Creatine monohydrate (CrM) and ß-hydroxy ß-methylbutyrate (HMB) are common ergogenic aids in the field of sports and are frequently used in an isolated way. However, there are a few studies that have investigated the effect of combining both supplements on different variables related to performance, with controversial results. Therefore, the main purpose of this study was to determine the efficacy and the degree of potentiation of 10 weeks of CrM plus HMB supplementation on sports performance, which was measured by an incremental test to exhaustion in elite male traditional rowers. In this placebo-controlled, double-blind trial, 10-week study, participants (n = 28) were randomized to a placebo group (PLG; n = 7), CrM group (0.04 g/kg/day of CrM; n = 7), HMB group (3 g/day of HMB; n = 7) and CrM-HMB group (0.04 g/kg/day of CrM plus 3 g/day of HMB; n = 7). Before and after 10 weeks of different treatments, an incremental test was performed on a rowing ergometer to calculate the power that each rower obtained at the anaerobic threshold (WAT), and at 4 mmol (W4) and 8 mmol (W8) of blood lactate concentration. There were no significant differences in WAT and W4 among groups or in body composition. However, it was observed that the aerobic power achieved at W8 was significantly higher in the CrM-HMB group than in the PLG, CrM and HMB groups (p < 0.001; η2p = 0.766). Likewise, a synergistic effect of combined supplementation was found for the sum of the two supplements separately at WAT (CrM-HMBG = 403.19% vs. CrMG+HMBG = 337.52%), W4 (CrM-HMBG = 2736.17% vs. CrMG+HMBG = 1705.32%) and W8 (CrM-HMBG = 1293.4% vs. CrMG+HMBG = 877.56%). In summary, CrM plus HMB supplementation over 10 weeks showed a synergistic effect on aerobic power (measured as WAT, W4, and W8) during an incremental test but had no influence muscle mass.

[Effects of acute supplementation with beta-alanine on a limited time test at maximum aerobic speed on endurance athletes]. / Efectos de la suplementación aguda con beta-alanina sobre una prueba de tiempo límite a velocidad aeróbica máxima en atletas de resistencia.

INTRODUCTION: Introduction: the beta-alanine (BA) is one of the ergogenic aid most used by athletes, but the majority of the studies center the research on chronic supplementation. Objectives: to determine the acute effect of BA supplementation on a limited time test (LTT) at maximum aerobic speed (MAS) on endurance athletes. Material and method: eleven endurance athletes (VO2max 61.6 ± 9.5 mLO2•kg-1•min-1) were part of the study. The study consisted of a double-blind, cross-over intra-subject design, and the BA supplementation was 30 mg•kg-1 or placebo (PL) 60 minutes before completing a LTT. The variables were: time and distance in LTT, and post-effort lactate concentrations ([La]) in minutes 1, 3, 5, 7, and 9. The Student's t test was used for the analysis and the size of the effect (SE) was measured through Cohen's d test. Results: the time on LTT showed significant differences between BA and PL (p = 0.047; SE = 0.48). No significant differences were seen between both groups (p = 0.071; SE = 0.48), and [La] showed significant differences between both groups in minutes 3, 5 and 7, respectively (p < 0.05). Conclusion: acute supplementation with BA showed a significant increase in the execution time in LTT in the intensities connected to MAS. Hence, acute supplementation with BA is an ergogenic aid that could be considered by resistance athletes in order to increase the athletic performance.

INTRODUCCIÓN: Introducción: la beta-alanina (BA) es una de las ayudas ergogénicas más utilizadas actualmente por deportistas, pero la mayoría de los estudios centran su investigación en la suplementación prolongada. Objetivos: determinar el efecto agudo de la suplementación con BA sobre una prueba de tiempo límite (PTL) a velocidad aeróbica máxima (VAM) en atletas de resistencia. Material y método: once atletas de resistencia (VO2máx 61,6 ± 9,5 mLO2•kg-1•min-1) fueron parte del estudio. El diseño fue doble ciego, cruzado intrasujeto, y la suplementación de BA fue de 30 mg•kg-1 o placebo (PL) 60 minutos antes de completar una PTL. Las variables fueron: tiempo y distancia en la PTL y concentraciones de lactato ([La]) postesfuerzo en los minutos 1, 3, 5, 7 y 9. Para el análisis se utilizó una prueba t de Student y el tamaño del efecto (TE) se realizó mediante la prueba d de Cohen. Resultados: el tiempo en la PTL evidenció diferencias significativas entre la BA y PL (p = 0,047; TE = 0,48). No se observaron diferencias significativas en distancia entre ambos grupos (p = 0,071; TE = 0,48) y las [La] evidenciaron diferencias significativas entre ambos grupos en los minutos 3, 5 y 7, respectivamente (p < 0,05). Conclusión: la suplementación aguda con BA evidenció aumentos significativos en el tiempo de ejecución en la PTL a intensidades correspondientes a VAM. Por lo anterior, la suplementación aguda con BA es una ayuda ergogénica que podría ser considerada por los atletas de resistencia para aumentar el rendimiento deportivo.

Six weeks of oral Echinacea purpurea supplementation does not enhance the production of serum erythropoietin or erythropoietic status in recreationally active males with above-average aerobic fitness.

The purpose of this study was to investigate the effect of 6 weeks of oral Echinacea purpurea supplementation on serum erythropoietin (EPO) and erythropoietic status. Twenty-four males (mean ± SE; age = 25.2 ± 1.4 years, height = 178.1 ± 1.4 cm, body mass = 78.1 ± 1.6 kg, body fat = 12.7 ± 0.9%, maximal oxygen uptake = 52.9 ± 0.9 mL·kg-1·min-1) were randomly grouped using a matched-pair, double-blind design and self-administered 8000 mg·day-1 of either E. purpurea (n = 12) or placebo (n = 12) for 42 consecutive days. Blood samples were collected prior to supplementation (day 0) and every 2 weeks during the supplementation period (days 14, 28, and 42) and were analyzed for EPO, red blood cell count, hemoglobin concentration, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin concentration. Separate 2 × 4 (group × time) factorial ANOVA with repeated measures on time were used to determine statistical differences with significance set at p ≤ 0.05. There were no significant interaction, group, or time effects observed for EPO or erythropoietic status markers for any of the measurement points (p ≤ 0.05). The present study indicated that 6 weeks of oral E. purpurea supplementation in recreationally active males with above average aerobic fitness did not enhance EPO or erythropoietic status. These findings are in contrast with previous reports of E. purpurea supplementation in untrained participants with average fitness levels, but consistent with observations in trained endurance athletes.

Test-retest reliability and criterion validity of a new Taekwondo Anaerobic Intermittent Kick Test.

BACKGROUND: The aim of this study was to determine the relative and absolute test-retest reliability and criterion validity of a new Taekwondo Anaerobic Intermittent Kick Test (TAIKT). METHODS: Twenty Tunisian elite Taekwondo athletes participated in this study (15 males and 5 females). Participants performed the TAIKT and the Running-based Anaerobic Sprint Test (RAST), twice (test and retest), on separate occasions three-week apart. Peak heart rate (HRpeak), blood lactate concentration [LaÖ¾], and rating of perceived exertion (RPE) were measured during each session. RESULTS: There was no significant difference between the test and retest of TAIKT and RAST for all performances and physiological variables, except for the absolute mean power (Pmean) of RAST. Test-retest results showed that the TAIKT and RAST were reliable. All TAIKT and RAST parameters had an ICC>0.90, SEM<5%, with the smallest worthwhile change slightly higher than SEM, with very small limits of concordance. Strong significant correlations were found between TAIKT and RAST parameters (Ppeak (r=0.81; r=0.70), Pmean (r=0.72; r=0.60) in (W and W·Kg-67 respectively), fatigue index (r=0.81), [LaÖ¾] (r=0.89) and RPE (r=0.78) at P<0.01, and HRpeak (r=0.55, at P<0.05)). CONCLUSIONS: The findings showed that the TAIKT can be considered as a valid and reliable specific test for assessing anaerobic power of Taekwondo athletes.

Can caffeine supplementation reverse the effect of time of day on repeated-sprint exercise performance?

The aim of this study was to evaluate if caffeine can reduce the negative influence of diurnal variations on repeated-sprint performance, in addition to investigating if caffeine in the afternoon would potentiate performance compared with the morning. Thirteen physically active men took part in this randomized, double-blind, placebo-controlled and crossover study. All participants underwent a repeated-sprint ability test (10 × 6 s cycle sprints, with 30 s of rest) at 60 min after ingestion of either 5 mg·kg-1 or placebo under 4 different conditions: morning with caffeine ingestion, morning with placebo ingestion, afternoon with caffeine ingestion, and afternoon with placebo ingestion. Total work, peak power (PP) and anaerobic power reserve (APR) were assessed. Oxygen uptake, heart rate, lactate concentration, and rating of perceived exertion were also measured during the repeated-sprint test. Total work (+8%, d = 0.2, small), PP (+6%, d = 0.2), and APR (+9%, d = 0.2) were significantly higher in the afternoon when compared with morning. However, physiological responses were not different between caffeine and placebo conditions. Repeated-sprint (10 × 6 s cycle sprint) performance was influenced by time of day, with lower performance in the morning compared with the afternoon. However, caffeine supplementation did not prevent the reduction in performance in the morning or improve performance in the afternoon.

The Synergistic Effects of Resveratrol combined with Resistant Training on Exercise Performance and Physiological Adaption.

The comprehensive studies done on resveratrol (RES) support that this polyphenol has multiple bioactivities and is widely accepted for dietary supplementation. Furthermore, regular exercise is known to have benefits on health and is considered as a form of preventive medicine. Although the vast majority of prior studies emphasize the efficacy of aerobic exercise in promoting physiological adaptions, other types of exercise, such as resistance exercise and high-intensity interval training (HIIT), may achieve similar or different physiological outcomes. Few studies have looked into the effectiveness of a combinational, synergistic approach to exercise using a weight-loading ladder climbing animal platform. In this study, ICR mice were allocated randomly to the RES and training groups using a two-way ANOVA (RES × Training) design. Exercise capacities, including grip strength, aerobic performance, and anaerobic performance, were assessed and the physiological adaptions were evaluated using fatigue-associated indexes that were implemented immediately after the exercise intervention. In addition, glycogen levels, muscular characteristics, and safety issues, including body composition, histopathology, and biochemistry, were further elucidated. Synergistic effects were observed on grip strength, anaerobic capacities, and exercise lactate, with significant interaction effects. Moreover, the training or RES may have contributed significantly to elevating aerobic capacity, tissue glycogen, and muscle hypertrophy. Toxic and other deleterious effects were also considered to evaluate the safety of the intervention. Resistance exercise in combination with resveratrol supplementation may be applied in the general population to achieve better physiological benefits, promote overall health, and promote participation in regular physical activities.