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2.
Sports (Basel) ; 11(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37888532

RESUMO

The effects of lifelong football training on bone health, body composition and physiological demands were evaluated. A total of 20 veteran football players (VPG; 73.4 ± 3.7 years) and 18 untrained age-matched men (CG; 75.6 ± 4.2 years) were enrolled. Whole-body and regional dual-energy X-ray absorptiometry scans of arms, legs, proximal femur and lower spine (L1-L4) were recorded in all participants. We observerd higher bone mineral density (BMD) in the whole-body, arms and femoral regions and higher bone mineral content (BMC) in the legs and lower spine compared to the CG (p < 0.05), also higher total lean body mass (p < 0.05) and lower total body fat percentage (p < 0.05), were found. No differences in food habits were evidenced between the VPG and the CG, as evaluated using 3-day food records. Resting heart rate (RHR), blood pressure (BP) and activity profile during a football match were recorded using a global positioning system only in the VPG. The mean heart rate (HR)of theoretical maximal HR (ThHRmax), and peak of ThHRmax were 83.9 ± 8.6% and 98.6 ± 10.2%, respectively; the mean of total distance covered was 3666 ± 721 m, and the means of accelerations and decelerations were 419 ± 61 and 428 ± 65, respectively. Lifelong participation in football training improves regional BMD and BMC in legs, femur and lumbar spine compared to the CG. A high number of intense actions in term of HR and accelerations and decelerations suggests an elevated energy expenditure that in turn correlates to the healthier body composition observed in the VPG compared to the CG.

3.
Eur J Sport Sci ; 23(12): 2291-2298, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37338107

RESUMO

ABSTRACTPrevious studies have shown that the school-based physical activity programme entitled "11 for Health" has been effective in improving the physical fitness, well-being and overall health profile of European children. The main purpose of the present study was to examine whether the "11 for Health" programme can have a positive impact on the physical fitness of primary school pupils in China. A total of 124 primary school pupils aged 9-11 years were included in the experiment, randomly divided into the experimental group (EG, n = 62) and the control group (CG, n = 62). EG carried out three weekly 35-minute sessions of small-sided football for a total of 11 weeks. All data were analysed by a mixed ANOVA with the Student-Newman-Keuls post hoc test. The results showed greater improvements (p<0.001) in EG than CG in relation to systolic blood pressure (-2.9 vs +2.0 mmHg). Moreover, greater improvements (all p<0.05) were observed in postural balance (13 vs 0%), standing long jump (5.0 vs 0.5%), 30-metre sprint (4.1 vs 1.3%) and Yo-Yo IR1C running performance (17% vs 6%). In both EG and CG, physical activity enjoyment was observed to be higher (P<0.05) compared to the start of the intervention with increases of 3.7 and 3.9 AU respectively. In conclusion, the study revealed that the "11 for Health" programme has positive effects on aerobic and muscular fitness, and it appears to be a relevant tool in the physical activity promotion in the Chinese school system.


The combined health education and football programme "11 for Health" was tested for the first time in the Chinese school system.The "11 for Health" programme had positive effects on the cardiovascular and muscular fitness of 9­11-year-old Chinese school children.The "11 for Health" programme seems to be a relevant tool for physical activity promotion in the Chinese school system, but further studies are warranted to test the implementation potential of the programme and the broadspectrum effects on physical activity enjoyment, wellbeing and health profile.


Assuntos
Futebol Americano , Corrida , Criança , Humanos , Aptidão Física/fisiologia , Exercício Físico , Teste de Esforço
4.
Artigo em Inglês | MEDLINE | ID: mdl-36497910

RESUMO

BACKGROUND: Aging and sedentary behavior are independent risk factors for non-communicable diseases. An active lifestyle and structured physical activity are positively associated with a healthier quality of life in the elderly. Here, we explored the proteomic/metabolomic muscular signature induced by lifelong football training associated with successful aging. METHODS: The study was performed on nine lifelong football players (67.3 ± 2.8 yrs) and nine aged-matched untrained subjects. We performed a proteomic/metabolomic approach on V. lateralis muscle biopsies; the obtained data were analyzed by means of different bioinformatic tools. RESULTS: Our results indicated that lifelong football training is able to enhance the muscles' oxidative capacity in the elderly by promoting fatty acids as preferential energetic substrates and hence determining a healthier body composition and metabolic profile; furthermore, we showed that the total polyamine content is higher in lifelong football players' muscle, enforcing the involvement of polyamines in muscle growth and hypertrophy. CONCLUSIONS: Lifelong football training, as a structured physical activity, significantly influences the expression of the proteins and metabolites involved in oxidative metabolism and muscle hypertrophy associated with successful aging.


Assuntos
Futebol Americano , Futebol , Idoso , Humanos , Qualidade de Vida , Proteômica , Músculo Esquelético/fisiologia
5.
Eur J Appl Physiol ; 122(8): 1929-1937, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35648211

RESUMO

PURPOSE: Studies have indicated upper body involvement during football, provoking long-term muscular adaptations. This study aimed at examining the acute metabolic response in upper and lower body skeletal muscle to football training organized as small-sided games (SSG). METHODS: Ten healthy male recreational football players [age 24 ± 1 (± SD) yrs; height 183 ± 4 cm; body mass 83.1 ± 9.7 kg; body fat 15.5 ± 5.4%] completed 1-h 5v5 SSG (4 × 12 min interspersed with 4-min recovery periods). Muscle biopsies were obtained from m. vastus lateralis (VL) and m. deltoideus (DE) pre- and post-SSG for muscle glycogen and metabolite analyses. Blood lactate samples were obtained at rest, middle and end of the SSG. RESULTS: Muscle glycogen in VL decreased (P < 0.01) by 21% and tended (P = 0.08) to decrease in DE by 13%. Muscle lactate increased in VL (117%; P < 0.001) and DE (81%; P < 0.001) during the game, while blood lactate rose threefold. Muscle ATP and PCr were unaltered, but intermuscular differences were detected for ATP at both time points (P < 0.001) and for PCr at pre-SSG (P < 0.05) with VL demonstrating higher values than DE, while muscle creatine rose in VL (P < 0.001) by 41% and by 22% in DE (P = 0.02). Baseline citrate synthase maximal activity was higher (P < 0.05) in VL compared to DE, whereas baseline muscle lactate concentration was higher (P < 0.05) in DE than VL. CONCLUSION: The upper body may be extensively involved during football play, but besides a rise in muscle lactate in the deltoideus muscle similar to the leg muscles, the present study did not demonstrate acute metabolic changes of an order that may explain the previously reported training effect of football play in the upper extremities.


Assuntos
Futebol , Adulto , Humanos , Masculino , Adulto Jovem , Trifosfato de Adenosina/metabolismo , Braço , Glicogênio/metabolismo , Lactatos , Perna (Membro) , Músculo Esquelético/fisiologia , Futebol/fisiologia
7.
Front Physiol ; 10: 132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30837897

RESUMO

Aging is a physiological process characterized by a progressive decline of biological functions and an increase in destructive processes in cells and organs. Physical activity and exercise positively affects the expression of skeletal muscle markers involved in longevity pathways. Recently, a new mechanism, autophagy, was introduced to the adaptations induced by acute and chronic exercise as responsible of positive metabolic modification and health-longevity promotion. However, the molecular mechanisms regulating autophagy in response to physical activity and exercise are sparsely described. We investigated the long-term adaptations resulting from lifelong recreational football training on the expression of skeletal muscle markers involved in autophagy signaling. We demonstrated that lifelong football training increased the expression of messengers: RAD23A, HSPB6, RAB1B, TRAP1, SIRT2, and HSBPB1, involved in the auto-lysosomal and proteasome-mediated protein degradation machinery; of RPL1, RPL4, RPL36, MRLP37, involved in cellular growth and differentiation processes; of the Bcl-2, HSP70, HSP90, PSMD13, and of the ATG5-ATG12 protein complex, involved in proteasome promotion and autophagy processes in muscle samples from lifelong trained subjects compared to age-matched untrained controls. In conclusion, our results indicated that lifelong football training positively influence exercise-induced autophagy processes and protein quality control in skeletal muscle, thus promoting healthy aging.

8.
Biomed Res Int ; 2017: 6204603, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28466014

RESUMO

Lack of motivation to exercise was reported as a major cause of sedentary behavior in adulthood. This descriptive study examines the acute physical and physiological demands of recreational team handball and evaluates whether it could be suggested as an exercise mode for fitness and health enhancement in 33-55-year-old untrained men. Time-motion, heart rate (HR), and blood lactate analyses were obtained from 4 recreational matches. Mean distance covered during the 60 min matches was 6012 ± 428 m. The players changed match activity 386 ± 70 times, of which high-intensity runs and unorthodox movements amounted to 59 ± 18 and 26 ± 26 per match, respectively. The most frequent highly demanding playing actions were jumps and throws. Match average and peak HR were 82 ± 6% and 93 ± 5% HRmax, respectively. Players exercised at intensities between 81 and 90% HRmax for 47% (28 ± 14 min) and >90% HRmax for 24% (14 ± 15 min) of total match time. Match average and peak blood lactate values were 3.6 ± 1.3 and 4.2 ± 1.2 mM, respectively. Recreational team handball is an intermittent high-intensity exercise mode with physical and physiological demands in the range of those found to have a positive effect on aerobic, anaerobic, and musculoskeletal fitness in adult individuals. Training studies considering recreational team handball as a health enhancing intervention are warranted.


Assuntos
Desempenho Atlético/fisiologia , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sedentário , Gravação em Vídeo
9.
Biomed Res Int ; 2017: 2719752, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28303248

RESUMO

We investigated the exercise intensity and fitness effects of frequent school-based low-volume high-intensity training for 10 months in 8-10-year-old children. 239 Danish 3rd-grade school children from four schools were cluster-randomised into a control group (CON, n = 116) or two training groups performing either 5 × 12 min/wk small-sided football plus other ball games (SSG, n = 62) or interval running (IR, n = 61). Whole-body DXA scans, flamingo balance, standing long-jump, 20 m sprint, and Yo-Yo IR1 children's tests (YYIR1C) were performed before and after the intervention. Mean running velocity was higher (p < 0.05) in SSG than in IR (0.88 ± 0.14 versus 0.63 ± 0.20 m/s), while more time (p < 0.05) was spent in the highest player load zone (>2; 5.6 ± 3.4 versus 3.7 ± 3.4%) and highest HR zone (>90% HRmax; 12.4 ± 8.9 versus 8.4 ± 8.0%) in IR compared to SSG. After 10 months, no significant between-group differences were observed for YYIR1C performance and HR after 2 min of YYIR1C (HRsubmax), but median-split analyses showed that HRsubmax was reduced (p < 0.05) in both training groups compared to CON for those with the lowest aerobic fitness (SSG versus CON: 3.2% HRmax [95% CI: 0.8-5.5]; IR versus CON: 2.6% HRmax [95% CI: 1.1-5.2]). After 10 months, IR had improved (p < 0.05) 20 m sprint performance (IR versus CON: 154 ms [95% CI: 61-241]). No between-group differences (p > 0.05) were observed for whole-body or leg aBMD, lean mass, postural balance, or jump length. In conclusion, frequent low-volume ball games and interval running can be conducted over a full school year with high intensity rate but has limited positive fitness effects in 8-10-year-old children.


Assuntos
Desempenho Atlético/fisiologia , Resistência Física , Aptidão Física , Criança , Dinamarca , Exercício Físico/fisiologia , Feminino , Futebol Americano , Frequência Cardíaca/fisiologia , Humanos , Masculino , Equilíbrio Postural/fisiologia , Corrida , Instituições Acadêmicas
10.
Eur J Appl Physiol ; 116(6): 1127-38, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27068158

RESUMO

PURPOSE: A decline in physical capacity takes place with increasing age that negatively affects overall physical function including work ability and the ability to perform typical activities of daily living (ADL). The overall aim of the present study was to determine the neuromuscular adaptations to long-term (1 year) football and strength training in older untrained adults, and to assess the concurrent effect on functional ADL capacity. METHODS: Twenty-seven healthy elderly males (68.2 ± 3.2 years) were randomly assigned to 12 months of either recreational football training (FT: n = 10), strength training (ST: n = 9) or served as inactive controls (CON: n = 8). Recreational football training consisted of small-sided training sessions whereas strength training consisted of high intensity exercises targeting the lower extremity and upper body. Maximal thigh muscle strength and rate of force development (RFD) were assessed with isokinetic dynamometry, while postural balance and vertical jumping performance were evaluated using force plate analysis. Furthermore, functional ability was evaluated by stair-ascent and chair-rising testing. RESULTS: A total of nine, nine and seven participants from FT, ST and CON, respectively, were included in the analysis. Both exercise regimens led to substantial gains in functional ability, evidenced by 24 and 18 % reduced stair-ascent time, and 32 and 21 % increased chair-rising performance in FT and ST, respectively (all P < 0.05). Long-term strength training led to increased concentric (14 %; P < 0.01) and isometric (23 %; P < 0.001) quadriceps and isometric hamstring strength (44 %; P < 0.0001), whereas football training mainly resulted in enhanced hamstring strength (18 %, P < 0.05) and RFD (89 %, P < 0.0001). CONCLUSIONS: Long-term (1 year) strength training led to increased quadriceps and hamstring strength, whereas the adaptations to football training mainly included enhanced strength and rapid force capacity of the hamstring muscles. Gains in functional ability were observed in response to both training regimens, evidenced by reduced stair-ascent time and increased chair-rising performance. Long-term football exercise and strength training both appear to be effective interventional strategies to improve factors of importance for ADL by counteracting the age-related decline in lower limb strength and functional capacity among old male adults. This could potentially be a way to improve work ability of senior workers.


Assuntos
Tolerância ao Exercício/fisiologia , Futebol Americano/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Treinamento Resistido/métodos , Atividades Cotidianas , Adaptação Fisiológica/fisiologia , Idoso , Terapia Combinada/métodos , Humanos , Estudos Longitudinais , Masculino , Força Muscular/fisiologia , Resultado do Tratamento
11.
J Sports Sci ; 32(20): 1958-1965, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25357189

RESUMO

Abstract The study examined the effect of caffeine supplementation on match activities and development of fatigue during a football match. In a randomised, double-blind cross-over design, two experimental football games separated by 7 days were organised between the junior teams of two professional football clubs (17.6 ± 1.1 years (±s), 71.7 ± 6.9 kg, 13.9% ± 5.0% body fat). The players ingested either a capsule of 6 mg · kg-1 b.w. caffeine or placebo (dextrose) 65 min prior to the matches. Match activities were assessed using the ZXY match analysis system, and a Yo-Yo intermittent recovery test-level 2 (Yo-Yo IR2) was conducted immediately post-game. Heart rate was monitored throughout the game, and blood samples were obtained at baseline, half-time and after the game. There were no differences between caffeine and placebo regarding total distance covered (10,062 ± 916 vs 9854 ± 901 m), high-intensity running (557 ± 178 vs 642 ± 240 m), sprinting distance (109 ± 58 vs 112 ± 69 m) or acceleration counts (123 ± 31 vs 126 ± 24). In both trials, players displayed lower (P < 0.05) values in total distance and acceleration counts in the last 15 min compared to all other 15-min periods of the matches. Post-game Yo-Yo IR2 performance was not different between game trials (caffeine: 829 ± 322 m; placebo 819 ± 289 m). In conclusion, oral caffeine administration does not appear to have an ergogenic effect in young football players during match play.

12.
J Sports Sci ; 32(13): 1300-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24787613

RESUMO

The aim was to investigate performance variables and indicators of cardiovascular health profile in elderly soccer players (SP, n = 11) compared to endurance-trained (ET, n = 8), strength-trained (ST, n = 7) and untrained (UT, n = 7) age-matched men. The 33 men aged 65-85 years underwent a testing protocol including measurements of cycle performance, maximal oxygen uptake (VO2max) and body composition, and muscle fibre types and capillarisation were determined from m. vastus lateralis biopsy. In SP, time to exhaustion was longer (16.3 ± 2.0 min; P < 0.01) than in UT (+48%) and ST (+41%), but similar to ET (+1%). Fat percentage was lower (P < 0.05) in SP (-6.5% points) than UT but not ET and ST. Heart rate reserve was higher (P < 0.05) in SP (104 ± 16 bpm) than UT (+21 bpm) and ST (+24 bpm), but similar to ET (+2 bpm), whereas VO2max was not significantly different in SP (30.2 ± 4.9 ml O2 · min(-1) · kg(-1)) compared to UT (+14%) and ST (+9%), but lower (P < 0.05) than ET (-22%). The number of capillaries per fibre was higher (P < 0.05) in SP than UT (53%) and ST (42%) but similar to ET. SP had less type IIx fibres than UT (-12% points). In conclusion, the exercise performance and cardiovascular health profile are markedly better for lifelong trained SP than for age-matched UT controls. Incremental exercise capacity and muscle aerobic capacity of SP are also superior to lifelong ST athletes and comparable to endurance athletes.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Tolerância ao Exercício/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento , Resistência Física/fisiologia , Futebol/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Pressão Sanguínea , Composição Corporal , Capilares/anatomia & histologia , Citrato (si)-Sintase/metabolismo , Teste de Esforço , Glicogênio/metabolismo , Frequência Cardíaca , Humanos , Masculino , Fibras Musculares Esqueléticas/metabolismo , Consumo de Oxigênio , Treinamento Resistido
13.
J Sports Sci ; 31(13): 1468-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23829604

RESUMO

We investigated the musculoskeletal health profile of elite female football players (ET) in comparison to untrained (UT) young women subjected to 16 weeks of football training (2 × 1 h per week). DXA scans, blood sampling, sprint testing and Flamingo postural balance testing were carried out for 27 Danish national team players and 28 untrained women, with eight women being tested after training. At baseline total BMD and BMC were 13% (1.305 ± 0.050 versus 1.159 ± 0.056 g · cm(-2)) and 23% (3047 ± 235 versus 2477 ± 526 g) higher (P <0.001) and leg BMD and BMC were 24 and 28% higher (P <0.01) in ET than in UT. Resting plasma osteocalcin was 45% higher in ET than in UT (28.8 ± 10.9 versus 19.9 ± 9.9 µg · L(-1), P <0.05). Total lean body mass was 14% higher (50.4 ± 3.3 versus 44.3 ± 4.0 kg) in ET compared with UT, with no difference in total body mass. The number of Flamingo test falls was 56-63% less (P <0.01) and 30 m sprinting speed was 31% faster (P <0.001) in ET than UT. After 16 weeks of football training for UT, lean body mass increased by 1.4 ± 0.5 kg and the number of left leg falls decreased by 29% (P <0.05). No significant changes occurred in BMD or BMC, but plasma osteocalcin increased (P <0.05) by 37%. In summary, elite women footballers have an impressive musculoskeletal health profile compared with untrained controls, but short-term football training seems to reduce the risk of falls and increase bone formation.


Assuntos
Composição Corporal , Densidade Óssea , Osteocalcina/sangue , Condicionamento Físico Humano/fisiologia , Aptidão Física , Equilíbrio Postural , Futebol/fisiologia , Adulto , Compartimentos de Líquidos Corporais/metabolismo , Peso Corporal , Dinamarca , Feminino , Futebol Americano , Humanos , Perna (Membro) , Força Muscular , Músculo Esquelético , Corrida , Adulto Jovem
14.
J Sports Sci ; 31(13): 1421-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23829646

RESUMO

This study examined the intermittent exercise performance and cardiovascular health profile in elite female football players in comparison to untrained young women, as well as a subgroup subjected to football training 2x1 h · week(-1) for 16 weeks. Twenty-seven Danish national team players (elite trained, ET) and 28 untrained women (UT) underwent dual-energy X-ray absorptiometry-scanning (DXA), comprehensive transthoracic echocardiography, treadmill and Yo-Yo Intermittent Endurance level 2 (IE2) testing. Eight women in UT were also tested after the football training period. Maximal oxygen uptake rate (VO2max), peak ventilation and peak lactate were 40, 18 and 51% higher (P< 0.01) in ET than UT, respectively. Cardiac dimensions and function were greater in ET than UT, with left ventricular diastolic diameter, right ventricular diastolic diameter, tricuspid annular plane systolic excursion (TAPSE) and peak transmitral flow in early diastole divided by peak transmitral flow velocity in late diastole during atrial contraction (E/A-ratio) being 13, 19, 27 and 41%, respectively, greater in ET than UT (P< 0.001 to< 0.05). Yo-Yo IE2 performance was 7-fold higher in ET than UT (1772 ± 508 vs. 234 ± 66 m, P< 0.001), fat mass was 51% lower (P< 0.001) and high density lipoprotein (HDL) cholesterol levels were 20% higher (P< 0.01). Sixteen weeks of football elevated VO2max and Yo-Yo IE2 performance by 16 and 40%, respectively, and lowered fat mass by 6%. Cardiac function was markedly improved by 16 weeks of football training with 26 and 46% increases in TAPSE and E/A ratio, respectively, reaching levels comparable to ET. In summary, elite female football players have a superior cardiovascular health profile and intermittent exercise performance compared to untrained controls, but short-term football training can markedly improve the cardiovascular health status.


Assuntos
Sistema Cardiovascular , Condicionamento Físico Humano/fisiologia , Resistência Física/fisiologia , Aptidão Física , Futebol/fisiologia , Tecido Adiposo/metabolismo , Adulto , HDL-Colesterol/sangue , Dinamarca , Teste de Esforço , Feminino , Futebol Americano , Coração/anatomia & histologia , Coração/fisiologia , Ventrículos do Coração , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio , Valva Tricúspide/fisiologia , Ventilação , Adulto Jovem
15.
J Sports Sci ; 30(13): 1337-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22867048

RESUMO

We examined performance, heart rate response and construct validity of the Yo-Yo IR2 test by testing 111 elite and 92 sub-elite soccer players from Norway and Denmark. VO2max, Yo-Yo IR1 and repeated sprint tests (RSA) (n = 51) and match-analyses (n = 39) were also performed. Yo-Yo IR2 and Yo-Yo IR1 performance was 41 and 25% better (P < 0.01) for elite than sub-elite players, respectively, and heart rate after 2 and 4 min of the Yo-Yo IR2 test was 20 and 15 bpm (9 and 6% HRmax), respectively, lower (P < 0.01) for elite players. RSA performance and VO2max was not different between competitive levels (P > 0.05). For top-teams, Yo-Yo IR2 performance (28%) and sprinting distance (25%) during match were greater (P < 0.05) than for bottom-teams. For elite and sub-elite players, Yo-Yo IR2 performance was correlated (P < 0.05) with Yo-Yo IR1 performance (r = 0.74 and 0.76) and mean RSA time (r = -0.74 and -0.34). We conclude that the Yo-Yo IR2 test has a high discriminant and concurrent validity, as it discriminates between players of different within- and between-league competitive levels and is correlated to other frequently used intermittent elite soccer tests.


Assuntos
Desempenho Atlético/fisiologia , Teste de Esforço/normas , Frequência Cardíaca , Resistência Física/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adolescente , Adulto , Dinamarca , Humanos , Noruega , Consumo de Oxigênio , Adulto Jovem
16.
Hum Mov Sci ; 31(4): 970-86, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22397814

RESUMO

The purpose of the present study was to evaluate the effect of contrasting training modalities on mechanical muscle performance and neuromuscular activity during maximal SSC (stretch-shortening cycle) countermovement jumps (CMJ). Bilateral countermovement jumping, surface electromyography (EMG) and muscle fiber size (CSA) were studied in untrained individuals (n=49, 21-45 yrs) pre and post 12 weeks of progressive heavy-resistance strength training (ST, n=8), recreational soccer training (SOC, n=15), high-intensity interval running (INT, n=7), continuous running (RUN, n=9) or continuation of an inactive life-style (CON, n=10). ST displayed shortened CMJ take-off time (p<.05) and increased (p<.05) maximal CMJ jump height, peak down- and upward velocity of center of mass (COM), rate of vertical force development (RFD: ΔF(Z)/Δt), peak power production, rate of power development (RPD), mean plantar flexor EMG and peak hamstring rate of EMG rise (RER). Peak quadriceps EMG rate of rise increased in SOC (p<.05). Moreover, ST and SOC demonstrated increased quadriceps muscle fiber CSA and lean leg mass. Positive relationships (r>.70) were observed following ST between training-induced changes in CMJ SSC muscle performance, neuromuscular activity and muscle fiber CSA, respectively. ST induced a more rapid CMJ take-off phase and elevated muscle power production, indicating a more explosive-type SSC muscle performance. No effects were detected in CMJ performance after continuous running, high-intensity interval running and recreational soccer, despite an increased muscle fiber CSA and quadriceps muscle activity in SOC. Enhanced neuromuscular activity in the hip extensors (hamstrings) and plantar flexors, and increased myofiber fiber size were responsible for the enhanced CMJ SSC muscle performance with ST.


Assuntos
Destreza Motora/fisiologia , Contração Muscular/fisiologia , Força Muscular/fisiologia , Recreação/fisiologia , Treinamento Resistido/métodos , Corrida/fisiologia , Futebol/fisiologia , Adulto , Humanos , Masculino , Músculo Esquelético/fisiologia , Miofibrilas/fisiologia , Junção Neuromuscular/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
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