RESUMO
Background: There is increasing awareness of the physiological effects of Ramadan intermittent fasting (RIF) in obese subjects. However, there are no data on the effects of RIF on plasma volume changes (ΔPV) in individuals with different body weights. Background and Objectives: This study investigated the effects of RIF on ΔPV in normal-weight (NW) and overweight (OW) adult men, and adult men with obesity (OB) and severe obesity (SO). Materials and Methods: Thirty-two male subjects (32) were divided into four groups (n = 8 per group) according to their body mass index (BMI): normal weight (NW) (BMI < 25 kg/m2; age = 27.4 ± 3.8), overweight (OW) (BMI between 25 and 29.9 kg/m2; age = 26.8 ± 3.7), obese subjects (OB) (BMI between 30 and 34.9 kg/m2; age = 25.6 ± 2.9), and severely obesity (SO) (BMI between 35 and 40 kg/m2; age = 24.0 ± 4.1). Blood samples were collected for 24 h on 4 different occasions, at T0 before the start of the Ramadan month, at T1 15 days after the start of Ramadan, at T2 one day after the end of Ramadan, and at T3 on the 21st day after the end of Ramadan to determine ΔPV. All groups completed their fasting rituals for the 30 days of Ramadan. Results: A significant group × time effect occurred for body mass (p = 0.001; ES = 0.53), BMI (p = 0.001; ES = 0.53), and body fat percentage (p = 0.001; ES = 0.52). Post hoc tests indicated reductions in body mass in OB and SO at T1 (p = 0.03; ES = 0.21 and p = 0.002; ES = 0.12) and T2 (p = 0.03; ES = 0.31 and p = 0.02; ES = 0.23), reductions in BMI in OB and SO at T1 (p = 0.04; ES = 0.35 and p = 0.03; ES = 0.42) and T2 (p = 0.03; ES = 0.52 and p = 0.005; ES = 0.48), and reductions in body fat percentage only in OB AT T1 (p = 0.002; ES = 0.31) and T2 (p = 0.001; ES = 0.17). A significant group × time effect occurred for hematocrit (p = 0.02; ES = 0.34), hemoglobin (p = 0.01; ES = 0.35), and ΔPV (p = 0.02; ES = 0.18). Post hoc tests indicated increases in hematocrit in OB at T2 (p = 0.03; ES = 0.36) and hemoglobin in OB and SO at T1 (p = 0.03; ES = 0.35 and p = 0.002; ES = 0.32) and T2 (p = 0.003; ES = 0.21 and p = 0.002; ES = 0.33). There were also increases in ΔPV in OB at T1 and T2 (p = 0.002; ES = 0.25 and p = 0.003; ES = 0.22) and in SO only at T2 (p = 0.02; ES = 0.37). Contrast analysis indicated that NW was significantly lower than the grand mean of OW, Ob, and SO for all anthropometric and PVV variables (all p < 0.05). Conclusions: The effects of RIF on ΔPV and anthropometric characters was greater in obese individuals compared to normal-weight and overweight participants, suggesting that the improvements in body composition and ΔPV produced by RIF could positively influence obesity.
Assuntos
Índice de Massa Corporal , Peso Corporal , Jejum , Islamismo , Volume Plasmático , Humanos , Masculino , Jejum/fisiologia , Adulto , Volume Plasmático/fisiologia , Peso Corporal/fisiologia , Obesidade/fisiopatologia , Obesidade/complicações , Sobrepeso/complicações , Sobrepeso/fisiopatologia , Jejum IntermitenteRESUMO
The aim of this study was to examine the effect of time of day on short-term maximal performance and psychological variables in young females. Fifteen active women participated in the study (age: 22 ± 3 years) and completed Hooper and the POMS-F questionnaires subsequently. In a randomized order, they performed a maximum of 30 s cycling exercise at two different times of day: in the morning at 07:00 h and in the afternoon at 16:00 h with a recovery period of 48 h. The digit cancellation test, countermovement jump (CMJ), squat jump (SJ) test, and the lower quarter Y balance test were performed at the beginning and at the end of each session. Our results showed that only peak power and mean power (p < 0.01) during the maximum 30 s cycling, reaching distances during the Y-balance (p < 0.05), Jump height in CMJ and SJ (p < 0.01) as well as attention, vigor, and stress scores (all p < 0.01) were higher in the afternoon than in the morning. Our results indicated a daily diurnal variation in short-term maximal performance and mood states in young athletic women with better performance observed during the afternoon.
RESUMO
The remarkable popularity of fitness trends like high intensity functional training (HIFT), choreographed high intensity classes (CHIC) and resistance (RT) trainings raises the question on their effect on cardio-respiratory, lactate removal rate, endurance and body composition responses. The purpose of this study was to assess and compare these effects. Ninety-five participants were randomly assigned into 16 weeks of these trainings, five sessions/week. Anthropometric and fitness tests were carried out before training (PRE), after eight (8W) and sixteen weeks (16W). Body composition measures demonstrated significant decrease in body fat percentage (p<0.001, d=0.17-0.54) for all groups and fat mass (p< 0.001, d= 0.26-0.53) for HIFT and CHIC in 8W,16W and in 16W for RT (p= 0.03, d= 0.14), also significant increase in fat free mass only in HIFT (p< 0.002, d= 0.06-0.21) and RT (p< 0.001, d= 0.17-0.33) in 8W,16W. Cardio-respiratory measures demonstrated significant improvements in maximal aerobic capacity for HIFT (p< 0.001, d= 0.58-1.26) and CHIC (p< 0.001, d= 0.45-1.21) in 8W,16W. Endurance tests demonstrated significant improvements in 8W,16W in aerobic endurance among HIFT (p< 0.001, d= 1.28-3.19) and CHIC (p< 0.001, d= 1.16-1.79), in muscle absolute endurance in three groups (p< 0.002, d= 0.14-1.17)and muscle relative endurance in HIFT (p< 0.02, d= 0.13-0.2)and RT (p= 0.03, d= 0.3) in 16W. We can conclude that HIFT and CHIC are effective for cardio-respiratory and endurance improvement and all three programs are effective in reducing body fat.
RESUMO
Background and Objectives: Whole-body electromyostimulation is under investigation as a potential aid for obesity-related health problems, supplementing a comprehensive, evidence-based obesity management strategy that includes lifestyle, diet, and exercise. The study investigated the impact of a whole-body electromyostimulation training program on physical performance and cardiometabolic markers in young obese females. Materials and Methods: Twenty-eight obese females, aged over 18 years with BMI over 30 and body fat over 28% and no underlying health conditions or medication, were divided into a whole-body electromyostimulation group (15 participants) and a control group (13 participants). The whole-body electromyostimulation program lasted 12 weeks, with two 20 min sessions weekly, using bipolar, rectangular current. Assessments pre and post intervention included body composition, blood pressure, lipid profile, C-reactive protein levels, maximal oxygen consumption, and jumping and sprint performance. Two-way ANOVA and t-tests were used for analysis. Results: Statistical analysis revealed significant (group × time) interactions for body composition, systolic blood pressure, maximal oxygen consumption, jumping and sprint performance, and plasma levels of lipids and C-reactive protein. Post hoc analyses for the whole-body electromyostimulation group indicated improvements in body composition indices (p < 0.01), systolic blood pressure (p = 0.003), maximal oxygen consumption (p = 0.010), and both jumping and 30 m sprint performance (p < 0.001 and p = 0.001, respectively) after the intervention. Furthermore, plasma levels of lipids (p < 0.01) and C-reactive protein (p = 0.002) showed significant improvements following the training program. In contrast, no significant changes were observed for these variables in the control group. Conclusions: A 12-week whole-body electromyostimulation program significantly improved body composition (skeletal muscle mass, body mass index, body fat, and waist circumference), physical performance (maximal oxygen consumption, jumping and sprint performance), and certain cardiometabolic (plasma level of lipids) and inflammatory markers (C-reactive protein) in obese young women. Further research is needed to explore the broader effects of whole-body electromyostimulation on physical and cardiometabolic health.
Assuntos
Doenças Cardiovasculares , Terapia por Estimulação Elétrica , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Proteína C-Reativa/metabolismo , Obesidade , Desempenho Físico Funcional , LipídeosRESUMO
BACKGROUND: Satisfaction of fundamental needs is an important concept in sport, but currently there is no tool in Arabic to measure this construct. Basic needs are often linked to high rates of motivation and performance. It is necessary to develop tools to assess psychological needs in the sport context. AIM: This study aimed to validate the Basic Needs Satisfaction in Sport Scale (BNSSS) in Arabic language across Tunisian athletes, and to test its psychometric properties (factorial structure, internal reliability, construct validity, and sensitivity). METHODS: Athletes in various sports participated in this study (370 men, 146 women; mean age 18.35) and voluntarily completed the Arabic version of the BNSSS-20. Both exploratory (EFA, N = 294; males: 68%; females: 32%; [14-18] = 182; [19-28] = 112) and confirmatory (CFA; N = 222; males: 76.6%; females: 23.4%; [14-18] = 103; [19-28] = 119) factor analyses were examined. RESULTS: Results from the EFA suggest that the BNSSS scale reflects the theoretical model well, with good internal consistency for all factors. All 20 items of BNSSS revealed excellent reliability (McDonald's omega = 0.773, Cronbach's α = 0.886, Gutmann's λ6 = 0.970) and good temporal stability (ICC = 0.84, 95% CI = 0.55-0.93) over a 4-week period. Likewise, the CFA fit indices were excellent. CONCLUSION: The BNSSS presented excellent fit to the theoretical model for all indices, confirming the factorial structure and providing validity of the instrument for Tunisian athletes.
Assuntos
Esportes , Masculino , Humanos , Feminino , Adolescente , Reprodutibilidade dos Testes , Esportes/psicologia , Atletas/psicologia , Idioma , Satisfação PessoalRESUMO
BACKGROUND: Sports performance is the result of an interaction of several variables, such as physical, technical, and psychological. The ability of athletes to use motivation, is an important predictor to achieve high performance in sport. SMS-II comprised 18 elements to measure six behavioral control factors. AIM: This study aims to validate an Arabic version of the revised sports motivation scale-II (SMS-II) and measure the psychometric properties of factorial structure, internal reliability, construct validity, and sensitivity. METHODS: A total of 780 athletes from different disciplines (432 men, 348 women; mean age = 18.97 years) participated in this study. Athletes voluntarily responded to the version of SMS-II. Factorial validity was established by principal component analysis. Both exploratory (EFA; N = 390; males: 52.6%; females: 47.4%; [13-18] = 172; [19-30] = 218) and confirmatory (CFA; N = 390; males: 58.2%; females: 41.8%; [13-18] = 247; [19-30] = 143) analyses were examined. RESULTS: The 18 SMS-II items revealed perfect reliability (McDonald's omega = 0.841, Cronbach's α = 0.858, Gutmann's λ6 = 0.952) and good temporal stability (ICC = 0.960, 95% CI = 0.915-0.980; r = 0.935, 95% CI = 0.889-0.963 at p < 0.001) over 4-week period. The CFA adjustment indices were perfect. CONCLUSION: The results tended to clarify all indices as perfect adjustments to the theoretical model, ensuring the confirmation of factor structure and construction validity regarding the Tunisian sports workforce.
Assuntos
Desempenho Atlético , Motivação , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Atletas/psicologia , Psicometria , Idioma , Inquéritos e QuestionáriosRESUMO
PURPOSE: During Ramadan month, Muslims often continue training to maintain their muscle performance. However, trainers should stress the importance of the time of day chosen for practicing resistance training (RT) during Ramadan fasting to avoid health and performance alteration. Thus, this study aimed to investigate the effects of the timing of RT during Ramadan intermittent fasting (RIF) on muscle strength and hypertrophy in healthy male adults. METHODS: Forty men were randomly allocated to 2 matched groups: 20 practicing whole-body RT in the late afternoon in a fasted state and 20 training in the late evening in a fed state (FED). Both groups performed 4 days per week of whole-body RT (â¼75%-85% 1-repetition maximum, 12 repetitions/3-4 sets) during RIF. Anthropometric measurements and 1-repetition-maximum test for the squats, deadlift, and bench press were measured. A cross-sectional area of the quadriceps and biceps brachii was examined using ultrasound scans. All measurements were taken at 4 time points: 24 hours before the start of Ramadan, on the 15th day of Ramadan, on the 29th day of Ramadan, and 21 days after Ramadan. RESULTS: Post hoc tests indicated significant preimprovement to postimprovement in FED at the 29th day of Ramadan for the 1-repetition-maximum test for the squats (P = .02; effect size = 0.21) and deadlift (P = .03; effect size = 0.24) when compared to 24 hours before the start of Ramadan. No significant changes were observed in the fasted-state group or for cross-sectional area for both groups. CONCLUSIONS: Practicing RT during RIF appears not to have adverse effects on muscle hypertrophy and strength no matter whether it is practiced in FED or fasted state. However, RT had greater effects on muscle strength when applied in FED. Our findings suggest that training sessions should be scheduled after breaking the fast during Ramadan.
Assuntos
Jejum , Treinamento Resistido , Adulto , Humanos , Masculino , Jejum/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Hipertrofia , IslamismoRESUMO
This article was published in Volume 62, issue 6 of publishing year 2022, with a mistake in Table II. The correct Table II is the one included in this erratum.
RESUMO
Molecular hydrogen (H2 gas) dissolved in water to produce Hydrogen-Rich Water. Hydrogen-Rich Water (HRW) is considered as ergogenic aid in different exercise modes. However, acute pre-exercise HRW ingestion effect is unclear regarding athlete performance. This study aimed at investigating acute effect of HRW ingestion on aerobic and anaerobic exercise performance. Twenty-two male amateur middle-distance runners volunteered to participate in this study. In a randomized, double-blind study design, all players ingested 500 mL of HRW or placebo (PLA) supplement 30 min before the start of the tests. Over 4 days, maximal aerobic speed of Vameval test (MAS), time to exhaustion at MAS (Tlim), squat jump (SJ), counter-movement jump (CMJ) and five jump test (5JT) were evaluated. Also, rate of perceived exertion (RPE) and peak heart rate (HRpeak) were measured during the aerobic tests. For Vameval test, HRW ingestion improved MAS, HRpeak and RPE compared with the placebo condition. For Tlim test, HRW ingestion demonstrated improvements in time to exhaustion, RPE and HRpeak. However, no significant change was observed between HW and placebo conditions in SJ, CMJ, 5JT. 500 mL of HRW can significantly improve HRpeak, time to exhaustion, RPE, with no significant effect on MAS, jumping performance in amateur endurance athletes.
RESUMO
The aim of this study was to investigate the effects of listening to preferred music during a warm up or exercise, on performance during a 6-min all-out exercise test (6-MT) in young adult males. Twenty-five healthy males volunteered to participate in this study. Following a within subject design, participants performed three test conditions (MDT: music during the test; MDW: music during the warm-up; WM: without music) in random order. Outcomes included mean running speed over the 6-min test (MRS6), total distance covered (TDC), heart rate responses (HRpeak, HRmean), blood lactate (3-min after the test), and the rating of perceived exertion (RPE); additionally, feeling scale scores were recorded. Listening to preferred music during running resulted in significant TDC (Δ↑10%, p=0.006, ES=0.80) and MRS6 (Δ↑14%, p=0.012, ES=1.02) improvement during the 6-MT, improvement was also noted for the warm-up with music condition (TDC:Δ↑8%, p=0.028, ES=0.63; MRS6:Δ↑8%, p=0.032, ES=0.61). A similar reverse "J-shaped" pacing profile was detected during the three conditions. Blood lactate was lower in the MDT condition by 8% (p=0.01, ES=1.10), but not the MDW condition, compared to MW. In addition, no statistically significant differences were found between the test sessions for the HR, RPE, and feeling scale scores. In conclusion, listening to music during exercise testing would be more beneficial for optimal TDC and MRS6 performances compared to MDW and WM.
RESUMO
AIM: To evaluate the effects of eight weeks of mat Pilates training on selected hematological parameters, i.e. white blood cell, neutrophils, monocyte, lymphocyte, hematocrit, hemoglobin as well as plasma volume variations in healthy, active women. METHODS: Twenty-eight women physical education students volunteered to participate in the present investigation. They were assigned to two groups: a Pilates training group (n = 14) that followed an 8-week Pilates training program, and a control group (n = 14). Blood samples were collected at rest at two separate occasions before and after Pilates training. RESULTS: The Pilates training group had higher values of plasma volume variations and lower values of white blood cell (19.4%), neutrophils (32%), hematocrit (4.3%) and hemoglobin (4.6%) compared to control group (p<0.05). CONCLUSION: The results of the present study suggested that Pilates training could be an effective strategy for increasing plasma volume variations and boosting immune system in healthy active women.
Assuntos
Técnicas de Exercício e de Movimento , Técnicas de Exercício e de Movimento/métodos , Feminino , Humanos , Educação Física e Treinamento , Volume PlasmáticoRESUMO
The purpose of this study was to examine the test-retest reliability, and convergent and discriminative validity of a new taekwondo-specific change-of-direction (COD) speed test with striking techniques (TST) in elite taekwondo athletes. Twenty (10 males and 10 females) elite (athletes who compete at national level) and top-elite (athletes who compete at national and international level) taekwondo athletes with an average training background of 8.9 ± 1.3 years of systematic taekwondo training participated in this study. During the two-week test-retest period, various generic performance tests measuring COD speed, balance, speed, and jump performance were carried out during the first week and as a retest during the second week. Three TST trials were conducted with each athlete and the best trial was used for further analyses. The relevant performance measure derived from the TST was the time with striking penalty (TST-TSP). TST-TSP performances amounted to 10.57 ± 1.08 s for males and 11.74 ± 1.34 s for females. The reliability analysis of the TST performance was conducted after logarithmic transformation, in order to address the problem of heteroscedasticity. In both groups, the TST demonstrated a high relative test-retest reliability (intraclass correlation coefficients and 90% compatibility limits were 0.80 and 0.47 to 0.93, respectively). For absolute reliability, the TST's typical error of measurement (TEM), 90% compatibility limits, and magnitudes were 4.6%, 3.4 to 7.7, for males, and 5.4%, 3.9 to 9.0, for females. The homogeneous sample of taekwondo athletes meant that the TST's TEM exceeded the usual smallest important change (SIC) with 0.2 effect size in the two groups. The new test showed mostly very large correlations with linear sprint speed (r = 0.71 to 0.85) and dynamic balance (r = -0.71 and -0.74), large correlations with COD speed (r = 0.57 to 0.60) and vertical jump performance (r = -0.50 to -0.65), and moderate correlations with horizontal jump performance (r = -0.34 to -0.45) and static balance (r = -0.39 to -0.44). Top-elite athletes showed better TST performances than elite counterparts. Receiver operating characteristic analysis indicated that the TST effectively discriminated between top-elite and elite taekwondo athletes. In conclusion, the TST is a valid, and sensitive test to evaluate the COD speed with taekwondo specific skills, and reliable when considering ICC and TEM. Although the usefulness of the TST is questioned to detect small performance changes in the present population, the TST can detect moderate changes in taekwondo-specific COD speed.
RESUMO
To examine the effects of two high-intensity intermittent training (HIIT) programs of varying intensities (100% vs. 110% of maximal aerobic velocity [MAV]) on metabolic, hormonal and inflammatory markers in young men. Thirty-seven active male volunteers were randomly assigned into: HIIT experimental groups (100% MAV [EG100, n = 9] and 110% MAV [EG110, n = 9]) and a control groups (CG100, n = 9 and CG110, n = 9). Particpants performed high intesity intermittent exercise test (HIIE) at 100% or 110% MAV. Venous blood samples were obtained before, at the end of HIIE and at 15 min of recovery, and before and after 8 weeks of HIIT programs. After training, Glucose was lower (p < 0.01) in EG100 (d = 0.72) and EG110 (d = 1.20) at the end of HIIE, and at 15 min recovery only in EG110 (d = 0.95). After training, Insulin and Cortisol were lower than before training in EG100 and EG110 at the end of HIIE (p < 0.001). After HIIT, IL-6 deceased (p < 0.001) in EG100 (d = 1.43) and EG110 (d = 1.56) at rest, at the end of HIIE (d = 1.03; d = 1.75, respectively) and at 15 min of recovery (d = 0.88;d = 1.7, respectively). This decrease was more robust (p < 0.05) in EG110 compared to EG100. After HIIT, TNF-α deceased (p < 0.001) in EG100 (d = 1.43) and EG110 (d = 0.60) at rest, at the end of HIIE (0.71 < d < 0.98) and at 15 min of recovery (0.70 < d < 2.78). HIIT with 110% MAV is more effective in young males on the improvements of some metabolic (Glucose), hormonal (Cortisol) and inflammatory (IL-6) markers at rest, at the end of HIIE and 15 min of recovery than training at 100 % MAV.
RESUMO
OBJECTIVES: To analyze biochemical markers, wellness status, and physical fitness in elite soccer players in relation to changes in training and match exposure during a congested period of match play. METHODS: Fourteen elite soccer players were evaluated 3 times (T1, T2, and T3) over 12 weeks (T1-T2: 6-wk regular period of match play and T2-T3: 6-wk congested period of match play). Players performed vertical jump tests, repeated shuttle sprint ability test, and the Yo-Yo Intermittent Recovery Test at T1, T2, and T3. Plasma C-reactive protein, creatinine, and creatine kinase were analyzed at T1, T2, and T3. Wellness status was measured daily using the Hopper questionnaire (delayed onset of muscle soreness, stress, fatigue, and sleep quality). Training session rating of perceived exertion was also recorded on a daily basis. RESULTS: A significant increase was found in stress, fatigue, delayed onset of muscle soreness scores, and Hopper index during the congested period (between T2 and T3) compared with the regular period (between T1 and T2) (.001 < P < .008, 0.8 < ES < 2.3). Between T2 and T3, significant relationships were found between the percentage variations (Δ%) of C-reactive protein, and Δ% of creatine kinase with the Hopper Index, and the Δ% of fatigue score. In addition, the Δ% of fatigue score and Δ% of delayed onset of muscle soreness score correlated with Δ% Yo-Yo Intermittent Recovery Test and Δ% best of repeated shuttle sprint ability test (.49 < r < P < .01). CONCLUSIONS: An intensive period of congested match play significantly compromised elite soccer players' physical fitness and wellness status. Elite soccer players' wellness status reflects declines in physical fitness during this period while biochemical changes do not.
Assuntos
Desempenho Atlético , Futebol , Biomarcadores , Proteína C-Reativa , Creatina Quinase , Fadiga , Humanos , Mialgia , Futebol/fisiologiaRESUMO
The aim of this study was to analyse the acute effects of velocity-based resistance training on the physical and functional performance of older adults. Twenty participants (70.4 ± 7.4 years) performed the deadlift exercise, in two different resistance training protocols. The moderate-velocity protocol (MV) predicted maximum loads so that the movement velocity during the concentric phase remained in the range of 0.5 to 0.7 m/s and the high-velocity protocol (HV) predicted maximum loads so that the movement velocity remained between 0.8 and 1.0 m/s. The jump height (cm), handgrip strength (kg), and time (s) to complete the functional tests were assessed before (baseline), and immediately (post), 24-h, and 48-h after the MV and HV protocols. Compared to baseline, both training protocols acutely led to a gradual reduction in walking velocity, with significant values 24 hours after training (p = 0.044), on the other hand, both protocols improved performance in the timed up and go test at post (p < 0.001) and in the sit-to-stand test at 48-h (p = 0.024), although there were no significant differences between them for any times analysed (p > 0.05). No other outcomes exhibited significant changes. Results indicate that neither of the protocols (MV and HV) led to significant impairments in physical function of the older adults, and can be recommended with the safety criterion of at least 48-h of rest between sessions.
RESUMO
BACKGROUND: The aim of this study was to research and compare the effect of Crossfit® (CF), LesMills® (LM) and traditional resistance (TRAD) training program on short performances. METHODS: Participants were assigned randomly into three groups and followed the training sessions allocated at the rate of five sessions/week for 16 weeks. A battery of tests including anthropometric and performance measures were carried out over three sessions: before training (T0), after eight weeks (T1) and sixteen weeks of training (T2). RESULTS: Findings indicated that strength tests demonstrated a significant time effect (P<0.001, η
Assuntos
Força Muscular , Treinamento Resistido , Exercício Físico , Humanos , Extremidade Inferior , Músculos , Extremidade SuperiorRESUMO
BACKGROUND: Young swimmers are rarely involved in training control, leading to inadequate volume and prescription of training intensities. This study aimed to examine the effect of prescribing and monitoring training intensities around critical velocity (CV) on 400 m front-crawl performance during an 8-weeks period. METHODS: Twenty young male swimmers (13.4±1.0 years) were randomly assigned into two groups. The experimental group (EG) used training monitoring based on intensities around CV (95, 100, 105 and 110% of CV), while for the control group (CG) different heart rate (HR) zones (EN1+, EN2, EN2+ and EN3) were used as an intensity criterion. The training volume was the same for both EG and CG. A maximal 400 m front-crawl test was performed before and after the 8-week period to determine CV intensities and to assess alternations in performance. The rate of perceived exertion (RPE) and HR values were also evaluated. RESULTS: Significant main effects of time were observed for T400, CV, HR and RPE. A significant group × time interaction was found for T400 (P=0.035, effect size = 1.07, moderate). Results revealed significant pre-to-postimprovements for both EG (from 328.46±26.25 to 305.88±20.09) and CG (from 329.07±25.24 to 314.75±19.87). A significant group × time interaction was also found for CV (P=0.005, effect size=1.51, large). Results revealed significant pre- to post improvements for both EG (from 1.126±0.08 to 1.207±0.07) and CG (from 1.124±0.08 to 1.173±0.07). CONCLUSIONS: Both training methods induced significant improvements in 400 m front-crawl performance with a greater degree for the training prescription and monitoring using CV intensities.
Assuntos
Natação , Humanos , Masculino , Natação/fisiologiaRESUMO
BACKGROUND: Osteoporosis causes bone fragility, increasing the risk of fractures. Evidence suggests a strong correlation between obesity and fracture risk. Physical training is known to enhance bone resistance and protect from fracture; however, its osteogenic effect in the presence of obesity remains unknown. OBJECTIVE: We sought to evaluate the influence of exercise training on bone health indices in individuals with obesity. METHODS: This systematic literature search was conducted using common electronic databases from inception - December 2019. The following key terms (and synonyms searched for by the MeSH database) were included and combined using the operators "AND," "OR," "NOT": [("body mass index" OR obesity OR obese OR overweight OR fat mass) AND ("bone mineral density" OR "bone mineral content" OR "peak bone mass" OR "mechanical loading" OR "Osteoporosis" OR "bone geometry" OR "bone resistance") AND ("exercise training" OR "physical training" OR "strength training," OR "resistance training" OR "aerobic training" OR "combined training")]. RESULTS: After screening, 10 studies (889 initial records) were included in the final analysis (8 different countries, 263 participants). Two studies investigated males, six females, and two, both sexes. The training duration was at least eight weeks with 2-3 sessions/week. Physical training displayed a significant trivial impact on the whole body (WB) BMD (0.13 SMD; 95% CI [0.00, 0.26], p = 0.046). Subgroup analyses indicated a significant small increase in the WB BMD (0.27 SMD; 95% CI [0.00, 0.53], p = 0.048) in the endurance training group, a non-significant trivial increase in the WB BMD (0.11 SMD; 95% CI [-0.06, 0.29], p = 0.203) in the resistance group, and a non-significant trivial increase in the WB BMD (0.03 SMD; 95% CI [-0.26, 0.32], p = 0.86) in the combined training group. In addition, a significant small decrease was found in the weight of trained subjects (-0.24 SMD; 95% CI [-0.42, -0.05], p = 0.011). CONCLUSION: Physical training has little to no effect on the WB BMD in subjects with overweight/obesity. Currently, insufficient evidence to advocate for any specific type of exercise for enhancing bone health exists for overweight/obese individuals. Investigations examining the impact of varying types of physical exercise on WB BMD of obese individuals are needed.
RESUMO
Multidirectional repeated sprints with quick changes-of-direction (CoD) are considered a key performance determinant in basketball. The objective of this study was to investigate the effects of a 12-week CoD sprint training program compared to regular basketball training on selected measures of physical fitness and physiological adaptations in male basketball players. Sixteen professional basketball players were randomly assigned to an intervention group (INT = 8) or an active control group (CON = 8). INT completed a 12-week CoD sprint training program with two sessions per week while CON continued their regular training. Training volume was similar between groups. Before and after the intervention, the two groups were evaluated for the repeated sprint ability test with CoD (IRSA5COD), the squat jump (SJ) and countermovement jump (CMJ) test, the five time-jump test (FJT) and change of direction t-test. Blood samples were taken before the beginning of the experimental protocol, after 4, 8 and 12 weeks to monitor the testosterone/cortisol ratio (T/C). For t-test, post-hoc tests revealed significant pre-to-post improvements for INT (3.4%; p = 0.001, ES = 0.91). For CMJ, post-hoc tests revealed a significant pre-to-post decrease for INT (-11.6%; p = 0.001, ES = 0.94), and a significant improvement for CON (4.96%; p = 0.014, ES = 0.60). For T/C ratio, post-hoc tests revealed a significant decrease after 12 weeks of training for INT (52.3%; p < 0.001; ES = 0.63). In conclusion, twelve weeks of CoD sprint training enhanced CoD performance but negatively affected vertical jump capacity in male basketball players. T/C ratio indicated that the physiological demands associated with INT were well-balanced.