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1.
Abstract

Boxing is a sport that comprises a wide variety of integrated offensive, defensive and counter-attack skills performed in an unpredictable environment. Mastering the variety of complex motor skills (CMS) that are required in a boxing match allows the player to employ the best motor performance in most positions of the actual game. This study aimed to assess the associations between implementing CMS versus simple motor skill (SMS) training and the subsequent changes in physical, technical and technical performance effectiveness (TPE) variables in junior boxers. We employed an experimental design that comprised two groups (each 20 males, mean age = 15.22±0.62 years). For 12 weeks, intervention boxers received CMS training, while controls received traditional SMS training. Physical, technical and TPE variables were measured before and after the training programs. Although the two groups were of similar abilities at baseline, there were statistically significant differences (P<0.05) between the intervention and control boxers in the post measures, to the advantage of the intervention group. In terms of absolute (i.e. differences in) or relative (i.e. ratios of) improvements, the intervention group exhibited more favourable values across the variables, and better performance. Developing CMS of junior boxers could contribute positively to their physical and technical abilities, and enhance their TPE.  相似文献   

2.
Abstract

In this study, we examined ratings of perceived exertion (RPE) and attentional focus during exercise in relation to telic and paratelic metamotivational dominance and state. Thirty regular exercisers (11 females, 19 males), of whom 10 were telic dominant (mean Paratelic Dominance Scale score=6.2±2.9), 10 paratelic dominant (mean PDS score=23.8±1.4), and 10 non-dominant (mean PDS score=15.4±0.7) completed two exercise trials. In the first trial, the participants completed a maximal ramped exercise test on a motorized treadmill to determine their gas exchange threshold (the speed at which determined exercise intensity of the subsequent trial). Throughout the second trial (a 30-min treadmill run), the participants reported their metamotivational state, RPE, and attentional focus (associative or dissociative) at 5-min intervals. Heart rate was recorded at 3, 8, 13, 18, 23, and 28 min and expired air was analysed for oxygen consumption (VO2) between 1–3, 6–8, 11–13, 16–18, 21–23, and 26–28 min. There was no main effect of dominance or dominance×time interaction on any variables (P >0.05). Oxygen consumption did not differ between states but RPE was higher in the telic than paratelic state at 25 and 30 min (t 28=2.87, P <0.05; t 26.77=3.88, P <0.05, respectively). Attentional focus was more associative in the telic than paratelic state at 20, 25, and 30 min (t 28=? 3.73, P <0.05; t 28=? 4.85, P <0.01; t 28=? 5.15, P <0.05, respectively) and heart rate was higher at 23 min in the telic state (t 27=3.40, P <0.05). During the latter stages of exercise, the telic metamotivational state, not dominance, was related to a more associative attentional focus and higher RPE. Our results support the use of reversal theory (Apter, 2001) to understand perceptual and cognitive responses during aerobic exercise, but an experimental design in which state is manipulated is needed to examine the effects of metamotivational dominance and state on perceptual and cognitive responses.  相似文献   

3.
Abstract

The purpose of this study was to compare the effects of a specific vibration programme with those of combined aerobic and resistance exercise training on bone mineral density (BMD), body composition, and muscular strength in post-menopausal women, over a period of 6 months. Thirty-two healthy, inactive post-menopausal women aged 46–62 years were divided into exercise (n = 10), vibration (n = 13), and control (n = 9) groups. The exercise group participated in a supervised programme of strength training at 70% of one-repetition maximum (1-RM) 2 days a week, and aerobic exercise at 70–85% of maximum heart rate one day a week. The vibration group performed vibration training 3 days a week (9 sets×45–80 s per session, 35–40 Hz, peak-to-peak amplitude of vertical vibration = 1.5 mm) on a vibration platform (NemesTM LCB, Bosco System). The BMD of the lumbar spine (L2–L4) was assessed using dual-energy X-ray absorptiometry, and muscle strength with the 1-RM method at baseline and after 6 months of intervention. The BMD of L2–L4 increased in the exercise group (P < 0.05), remained steady in the vibration group, and decreased in the control group (P < 0.05). Muscular strength of leg-extension and leg-curl exercise improved by 28% and 25.5% (P < 0.01) in the exercise group and by 13% (P < 0.01) and 20.5% (P < 0.001) in the vibration group, respectively. The results indicate that conventional training contributed to the increase in BMD of L2–L4, while the vibration programme helped to maintain BMD in post-menopausal women. Both training programmes were efficient in improving muscle strength.  相似文献   

4.
Abstract

The aim of this study was to investigate whether weight categories prevent young athletes from being exposed to a relative age effect. The dates of birth of all French female (n = 727) and male (n = 5440) amateur boxers who participated in the 2010–2011 season were collected from the federation database. The dates of birth of all French male professional boxers (n = 354) were also collected. The results show an absence of a relative age effect among French female and male amateur boxers. The results also show an absence of this phenomenon among French male professional boxers. The male 18–18+ age category reveal an inverse relative age effect. This inverse relative age effect might be interpreted as the result of a strategic adaptation from relatively younger children who shift from one sport to another where there are weight categories in order to ensure fair competition. The results of this study suggest that the weight category system is a possible solution within the relative age effect phenomenon.  相似文献   

5.
Abstract

Orienteering is a sport in which it is common for most participants to be aged over 40 years, but research into the demands of the sport has focused almost exclusively on elite participants aged 21–35 years. The aim of the present study was to examine the heart rate responses of older male orienteers. Thirty-nine competitive male orienteers were divided into three groups: group 1 (international competitive standard, n=11, age 21–67 years), group 2 (national competitive standard, n=15, age 24–66 years) and group 3 (club competitive standard, n=13, age 23–60 years). Each participant had his heart rate monitored during two orienteering races of contrasting technical difficulty. The results were analysed using analysis of covariance, with age as a covariate, and Pearson product-moment correlation coefficients to determine whether age was related to the observed heart rate responses. The groups did not differ in their peak (175±12 beats · min?1, P=0.643) or mean (159±13 beats · min?1, P=0.171) heart rates during the races. There was a decline of 6 beats · min?1 · decade?1 (P=0.001) for peak heart rate and 5 beats · min ?1·decade?1 (P<0.001) for mean heart rate. Mean heart rates were 86±6% of the participants' maximal heart rates and were not associated with age. The orienteers in group 1 displayed a lower (P<0.005) within-race standard deviation in heart rate (6±2 beats · min?1) than those in groups 2 and 3 (10±3 and 10±4 beats · min?1, respectively). In conclusion, the mean heart rates indicated that all three groups of orienteers ran at a relative high intensity and the international competitive standard orienteers displayed a less variable heart rate, which may have been related to fewer instances of slowing down to relocate and being able to navigate while running at relatively high speeds.  相似文献   

6.
Abstract

This study examined the influence of match-related fatigue on physical and technical skill performance in ball playing positions at two different levels of rugby league competition. Time-motion analyses were performed using global positioning systems from 6 elite National Rugby League (NRL) and 11 junior elite National Youth Competition (NYC) players from 45 matches. A standardised 5-point technical coding criteria was used to qualitatively assess skill involvements during match-play. The distance travelled in the 0–5 and 40–45 min period were significantly higher compared to the 30–35, 35–40, 70–75 and 75–80 min periods (P < 0.001). Skill rating and involvements were higher in the 0–5 and 40–45 min compared to 70–75 and 75–80 min periods (P < 0.001 and P < 0.001, respectively).There was no significant difference in the number of physical collisions between the 5-min periods (P = 0.051). Following the peak 5-min bout of exercise intensity there were reductions in distance (P < 0.001), quality of skill involvements (P < 0.001), number of involvements (P < 0.001) and collisions (P < 0.001). Elite NRL and NYC “ball players” exhibit reductions in physical performance towards the end of matches and following brief periods of intense exercise. There also appears to be a reduction in technical performance for NRL and NYC ball players, which may be attributable to match-related fatigue.  相似文献   

7.
This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration.  相似文献   

8.
The effects of pomegranate extract (PE) supplementation were evaluated on high-intensity exercise performance, blood flow, vessel diameter, oxygen saturation (SPO2), heart rate (HR), and blood pressure (BP). In a randomized, crossover design, nineteen recreationally resistance-trained participants were randomly assigned to PE (1000?mg) or placebo (PL), which were consumed 30?min prior to a repeated sprint ability (RSA) test and repetitions to fatigue (RTF) on bench and leg press. The RSA consisted of ten six-second sprints on a friction-loaded cycle ergometer with 30?s recovery. Brachial artery blood flow and vessel diameter were assessed by ultrasound. Blood flow, vessel diameter, SPO2, HR, and BP were assessed at baseline, 30?min post ingestion, immediately post exercise (IPost), and 30?min post exercise (30minPost). With PE, blood flow significantly increased IPost RSA (mean difference?=?18.49?mL?min?1; P?<?.05), and IPost and 30minPost RTF (P?<?.05) according to confidence intervals (CI). Vessel diameter increased significantly 30minPost RSA according to CI and resulted in a significant interaction IPost and 30minPost RTF (P?<?.05). With PE, according to CI, average and peak power output increased significantly in sprint 5 of the RSA (P?<?.05). There was no significant difference between PE and PL for bench (P?=?.25) or leg press (P?=?.15) repetitions. Acute PE supplementation enhanced vessel diameter and blood flow, suggesting possible exercise performance enhancement from increased delivery of substrates and oxygen. The acute timing and capsule form of PE may be advantageous to athletic populations due to ergogenic effects, taste, and convenience.  相似文献   

9.
Nine well-trained, unacclimatized female hockey players performed the Loughborough Intermittent Shuttle Test (LIST) interspersed with three field hockey skill tests in hot (30°C, 38% relative humidity) and moderate (19°C, 51% relative humidity) environmental conditions. Field hockey skill performance declined in both the hot and moderate conditions following 30 and 60?min of the LIST compared with pre-LIST values (P <?0.01). This decrement in performance was compounded in the hot environment with a 6% poorer performance in the heat recorded for the second skill test at 30?min (P <?0.05, hot 101.7?±?3.6 vs moderate 95.7?±?2.9?s; mean ±?s x). However, no difference was found in the decision-making element of the skill test. Fifteen-metre sprint times were slower in the hot condition (P <?0.01). In the hot environment, rectal temperature (P?<?0.01), perceived exertion (P?<?0.05), perceived thirst (P?<?0.01), blood glucose concentration (P?<?0.05) and serum aldosterone concentration (P?<?0.01) were higher. Estimated mean (?±?s x) sweat rate was higher in the hot trial (1.27?±?0.10?l?·?h?1) than in the moderate trial (1.05?±?0.12?l?·?h?1) (P?<?0.05). Body mass was well maintained in both trials. No differences in serum cortisol, blood lactate, plasma volume or plasma ammonia concentrations were found. These results demonstrate that field hockey skill performance is decreased following intermittent high-intensity shuttle running and that this decrease is greater in hot environmental conditions. The exact mechanism for this decrement in performance remains to be elucidated, but is unlikely to be due to low glycogen concentration or dehydration.  相似文献   

10.
The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13–17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6–10 repetitions at 60–70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50–80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.  相似文献   

11.
Abstract

The aim of this study was to examine the effect of playing formation on high-intensity running and technical performance during elite soccer matches. Twenty English FA Premier League games were analysed using a multiple-camera computerized tracking system (n = 153 players). Overall ball possession did not differ (P > 0.05) between 4–4–2, 4–3–3 and 4–5–1 formations (50%, s = 7 vs. 49%, s = 8 vs. 44%, s = 6). No differences were observed in high-intensity running between 4–4–2, 4–3–3 and 4–5–1 formations. Compared with 4–4–2 and 4–3–3 formations, players in a 4–5–1 formation performed less very high-intensity running when their team was in possession (312 m, s = 196 vs. 433 m, s = 261 vs. 410 m, s = 270; P < 0.05) but more when their team was not in possession (547 m, s = 217 vs. 461 m, s = 156 vs. 459 m, s = 169; P < 0.05). Attackers in a 4–3–3 performed ～30% more (P < 0.05) high-intensity running than attackers in 4–4–2 and 4–5–1 formations. However, the fraction of successful passes was highest in a 4–4–2 (P < 0.05) compared with 4–3–3 and 4–5–1 formations. The results suggest that playing formation does not influence the overall activity profiles of players, except for attackers, but impacts on very high-intensity running activity with and without ball possession and some technical elements of performance.  相似文献   

12.
The purpose of this investigation was to measure the interface pressure exerted by lower body sports compression garments, in order to assess the effect of garment type, size and posture in athletes. Twelve national-level boxers were fitted with sports compression garments (tights and leggings), each in three different sizes (undersized, recommended size and oversized). Interface pressure was assessed across six landmarks on the lower limb (ranging from medial malleolus to upper thigh) as athletes assumed sitting, standing and supine postures. Sports compression leggings exerted a significantly higher mean pressure than sports compression tights (P < 0.001). Oversized tights applied significantly less pressure than manufacturer-recommended size or undersized tights (P < 0.001), yet no significant differences were apparent between different-sized leggings. Standing posture resulted in significantly higher mean pressure application than a seated posture for both tights and leggings (P < 0.001 and P = 0.002, respectively). Pressure was different across landmarks, with analyses revealing a pressure profile that was neither strictly graduated nor progressive in nature. The pressure applied by sports compression garments is significantly affected by garment type, size and posture assumed by the wearer.  相似文献   

13.
Abstract

The aim of this study was to examine the acute response to plasma and salivary cortisol and testosterone to three training protocols. Ten trained endurance athletes participated in three experimental trials, such as interval training (INT), tempo run (TEMP) and bodyweight-only circuit training (CIR), on separate days. Blood and saliva samples were collected pre- and 0, 15, 30 and 60 min post-exercise. Peak post-exercise salivary cortisol was higher than pre-exercise in all trials (P < 0.01). After INT, salivary cortisol remained elevated above pre-exercise than 60 min post-exercise. Salivary testosterone also increased post-exercise in all trials (P < 0.05). Plasma and salivary cortisol were correlated between individuals (r = 0.81, 0.73–0.88) and within individuals (r = 0.81, 0.73–0.87) (P < 0.01). Plasma and salivary testosterone was also correlated between (r = 0.57, 0.43–0.69) and within individuals (r = 0.60, 0.45–0.72), (P < 0.01). Peak cortisol and testosterone levels occurred simultaneously in plasma and saliva, but timing of post-exercise hormone peaks differed between trials and individuals. Further investigation is required to identify the mechanisms eliciting an increase in hormones in response to CIR. Furthermore, saliva is a valid alternative sampling technique for measurement of cortisol, although the complex, individual and situation dependent nature of the hormone response to acute exercise should be considered.  相似文献   

14.
Abstract

Adiponectin mRNA and plasma concentrations were reduced in obesity. Exercise training may reduce the adipose tissue (AT), although it is not well known, whether exercise – induced change in AT, increases adiponectin mRNA expression and plasma concentrations or not. Therefore, the purpose of this study was to examine the effects of short-term lifestyle activity modification (LAM) on adiponectin mRNA and plasma concentrations. Sixteen obese and overweight middle-aged men (age, 35–50 years) with type 2 diabetes participated in this study. The subjects were randomly assigned to LAM group (n=8) or control group (n=8). The subjects in LAM group walked two miles in 30 min on a treadmill on 4 days per week for 12 weeks according to the guidelines of the Centers for Disease Control and Prevention and American College of Sports Medicine. The results showed that body mass, body mass index, central visceral adipose tissue and subcutaneous adipose tissue volume and hip and thigh subcutaneous adipose tissue (hip and thigh SAT) volume were decreased in the LAM group compared to the control group (P<0.05). Adiponectin mRNA in abdominal and gluteal subcutaneous AT were increased significantly in the LAM group compared to the control group (P<0.05), while plasma adiponectin concentrations, hs-CRP and insulin resistance did not change significantly. In conclusion, adiponectin mRNA levels increase after 12 weeks of LAM; however, plasma adiponectin levels were not affected by this protocol in obese and overweight middle-aged men with type 2 diabetes.  相似文献   

15.
Abstract

This study aimed to analyse whether increasing the eccentric overload (EO) during resistance training, in terms of range of motion and/or velocity using an electric-motor device, would induce different muscle adaptations than conventional flywheel-EO resistance training. Forty physically active university students (21.7?±?3.4 years) were randomly placed into one of the three training groups (EX1, EX2, FW) and a control group without training (n?=?10 per group). Participants in the training groups completed 12 sessions (4 sets of 7 repetitions) of iso-inertial single-leg squat training over 6 weeks for the dominant leg. Resistance was generated either by an electric-motor device at two different velocities for the eccentric phase; 100% (EX1) or 150% (EX2) of concentric speed, or by a conventional flywheel device (FW). Thigh lean tissue mass, unilateral leg press one-repetition maximum (1-RM), unilateral muscle power at different percentages of the 1-RM and bilateral/unilateral vertical jump were assessed before and after the 6-week training. There were significant (p?<?0.05–0.001) main effects of time in the 3 training groups, indicating increased thigh lean tissue mass (2.5–5.8%), 1-RM load (22.4–30.2%), vertical jump performance (9.1–32.9%) and muscle power (8.8–21.7%), without differences across experimental groups. Participants in the control group did not improve any of the variables measured. In addition, EX2 showed greater gains in eccentric average peak power during training than EX1 and FW (p?<?0.001). Despite the different EO offered, 6 weeks of resistance training using flywheel or electric-motor devices induced similar significant gains in muscle mass, strength, muscle power and vertical jump.  相似文献   

16.
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17.
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18.
It is believed that sport massage after intensive exercise might improve power and perceptual recovery in athletes. However, few studies have been done in this area. This study aimed to examine the effect of massage on the performance of bodybuilders. Thirty experienced male bodybuilders were randomly assigned to either a massage group (n = 15) or a control group (n = 15). Both groups performed five repetition sets at 75–77% of 1RM of knee extensor and flexor muscle groups. The massage group then received a 30-min massage after the exercise protocol while the control group maintained their normal passive recovery. Criteria under investigation included: plasma creatine kinase (CK) level, agility test, vertical jump test, isometric torque test, and perception of soreness. All variables were measured over 6 time periods: baseline, immediately after the DOMS inducing protocol, right after the massage, and 24, 48, and 72 h after the massage. Both groups showed significant (P < .001) decreases in jumping, agility performance, and isometric torque, but significant (P < .001) increases in CK and muscle soreness levels. The massage group in general demonstrated a better recovery rate. As such, a post-exercise massage session can improve the exercise performance and recovery rate in male bodybuilders after intensive exercise.  相似文献   

19.
Abstract

Tart Montmorency cherry concentrate (MC) has been reported to attenuate the symptoms of exercise-induced muscle damage (EIMD) and to accelerate exercise recovery, which has been attributed to its high anti-inflammatory and antioxidant properties. Although these data are promising, there are no data regarding exclusively female populations. Therefore, the aim of this investigation was to examine the efficacy of MC on recovery following EIMD in females. In a randomised, double-blind, placebo-controlled study, twenty physically active females (mean?±?SD age 19?±?1?y; stature 167?±?6?cm; body mass 61.4?±?5.7?kg) consumed MC or a placebo (PL) for eight days (30?mL twice per day). Following four days of supplementation, participants completed a repeated-sprint protocol and measures of muscle soreness (DOMS), pain pressure threshold (PPT), limb girth, flexibility, muscle function, and systemic indices of muscle damage and inflammation were collected pre, immediately post (0?h) and 24, 48 and 72?h post-exercise. Time effects were observed for all dependent variables (p?<?0.05) except limb girth and high sensitivity C-reactive protein. Recovery of countermovement jump height was improved in the MC group compared to PL (p?=?0.016). There was also a trend for lower DOMS (p?=?0.070) and for higher PPT at the rectus femoris (p?=?0.071) in the MC group. The data demonstrate that MC supplementation may be a practical nutritional intervention to help attenuate the symptoms of muscle damage and improve recovery on subsequent days in females.  相似文献   

20.
Abstract

This study examined the effects of a 6-week intermittent exercise training, at different intensities, on body composition, functional walking and aerobic endurance in overweight children. Forty-eight overweight children (age: 10.4 ± 0.9 years) were randomly assigned to either intervention or control group. Lower and higher intensity intermittent exercise groups (LIIE and HIIE) performed intermittent running three times a week. LIIE performed more intervals at a lower intensity [16 intervals at 100% of individual maximal aerobic speed (MAS), 8 minutes in total], and HIIE performed fewer intervals at a higher intensity (12 intervals at 120% of MAS, 6 minutes in total). Each interval consisted of a 15-second run at the required speed, followed by a 15-second passive recovery. After 6 weeks, HIIE had a significantly (p < 0.05) higher percentage reduction in sum of skinfolds (i.e. calf and triceps), and significantly (p < 0.05) fewer steps during the functional obstacle performance, as compared with LIIE and control group. Significant improvement (p < 0.05) was found in intermittent aerobic endurance for HIIE as compared to the control group. Higher intensity intermittent training is an effective and time-efficient intervention for improving body composition, functional walking and aerobic endurance in overweight children.  相似文献   

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