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1.
This study investigated whether haematological markers differ between young and masters marathon participants, running at similar performance levels. Nine young (31.89 ± 4.96 years) and eight masters (63.13 ± 4.61 years) runners participated. At five time points (pre-race through 54 h post-race), a complete blood cell count, basic metabolic panel and creatine kinase (CK) isoenzyme panel were assessed. Race performance was standardised using the World Masters Association Age Grading Performance Tables. Total CK levels were elevated for all participants at all time points post-race (P < 0.001). The CK-isoenzyme MB% was elevated across groups at 6, 30 and 54 h post-race (P < 0.01, P < 0.01 and P < 0.05), with masters runners having a higher CK-MB% at 30 and 54 h (P < 0.05, P < 0.05). Total white blood cell and neutrophil counts were elevated through 6 h post-race (P < 0.001), with higher levels found in younger runners (P < 0.001). When considering all blood work, masters runners had a higher number of abnormal values at 6, 30 and 54 h post-race (P < 0.05, P < 0.01 and P < 0.05). In conclusion, masters runners demonstrated sustained CK-MB elevation, which may suggest greater cardiac stress. However, future studies using additional cardiac markers should be completed to confirm these findings. In addition, masters runners showed an increased number of laboratory values outside normal range, indicating the body’s reduced capacity to respond to marathon running.  相似文献   

2.
We tested the hypothesis that changes in serum cartilage oligomeric matrix protein (COMP), tumour necrosis factor α (TNF-α), interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) concentration after regular endurance training and running a marathon race depend on body mass index (BMI) and/or on marathon performance. Blood samples were collected from 45 runners of varying BMI and running experience before and after a 10-week marathon training programme and before, immediately and 24 h after a marathon race. Serum biomarker concentrations, BMI and marathon finishing time were measured. The mean (95% confidence interval (CI)) changes from before to immediately after the marathon were COMP: 4.09 U/L (3.39–4.79 U/L); TNF-α: ?1.17 mg/L (?2.58 to 0.25 mg/L); IL-6: 12.0 pg/mL (11.4–12.5 pg/mL); and hsCRP: ?0.08 pg/mL (?0.14 to ?0.3 pg/mL). The mean (95% CI) changes from immediately after to 24 h after the marathon were COMP: 0.35 U/L (?0.88 to 1.57 U/L); TNF-α: ?0.43 mg/L (?0.99 to 0.13 mg/L); IL-6: ?9.9 pg/mL (?10.5 to ?9.4 pg/mL); and hsCRP: 1.52 pg/mL (1.25–1.79 pg/mL). BMI did not affect changes in biomarker concentrations. Differences in marathon finishing time explained 32% of variability in changes in serum hsCRP and 28% of variability in changes in serum COMP during the 24 h recovery after the marathon race (P < 0.001). Slower marathon finishing time but not a higher BMI modulates increases in pro-inflammatory markers or cartilage markers following a marathon race.  相似文献   

3.
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   

4.
Abstract

The aim of this study was to investigate the effects of a single bout of whole-body vibration (WBV) on running gait. The running kinematic of sixteen male marathon runners was assessed on a treadmill at iso-efficiency speed after 10 min of WBV and SHAM (i.e. no WBV) conditions. A high-speed camera (210 Hz) was used for the video analysis and heart rate (HR) was also monitored. The following parameters were investigated: step length (SL), flight time (FT), step frequency (SF), contact time (CT), HR and the internal work (WINT). Full-within one-way analysis of variance (ANOVA) of the randomised crossover design indicated that when compared to SHAM conditions, WBV decreased the SL and the FT by ~4% (P < 0.0001) and ~7.2% (P < 0.001), respectively, and increased the SF ~4% (P < 0.0001) while the CT was not changed. This effect occurred during the first minute of running: the SL decreased ~3.5% (P < 0.001) and SF increased ~3.3% (P < 0.001). During the second minute the SL decreased ~1.2% (P = 0.017) and the SF increased ~1.1% (P = 0.02). From the third minute onwards, there was a return to the pre-vibration condition. The WINT was increased by ~4% (P < 0.0001) during the WBV condition. Ten minutes of WBV produced a significant alteration of the running kinematics during the first minutes post exposure. These results provide insights on the effects of WBV on the central components controlling muscle function.  相似文献   

5.
This study determined the effect of 8 wk of mindfulness training (MT) on salivary cortisol (sCort) and rate of salivary Immunoglobulin-A (sIgA) secretion in wheelchair-basketball players during a competition period. The mindful group completed 8 weeks of MT in addition to training and competition. sCort and rate of sIgA secretion were measured at baseline, at 2-week intervals, the end and 2 weeks following the intervention. A significant time and group interaction was observed for sCort (F = 3.297, P = 0.040, ES = 0.191); sCort increased in the control group from MT-BL to MT-2wk (P = 0.001) and remained significantly elevated at MT-4wk (P = 0.013) and MT-6wk (P = 0.002). sCort decreased from MT-6wk to MT-8wk (P < 0.001) and concentrations were not different at MT-8wk and Post-2wk to MT-BL (P > 0.05). Mindful group sCort increased from MT-BL to MT-2wk (P = 0.042) but decreased to concentrations no different to MT-BL for the rest of the intervention period (P > 0.05). There were no group differences in rate of sIgA secretion during the intervention (P = 0.810). It was concluded that 8 weeks of MT attenuated the increase in sCort associated with the competition period.  相似文献   

6.
Several genetic loci have been associated with risk of Achilles tendon pathology (ATP) within South African and Australian populations. The aim of this study was, therefore, to evaluate eight previously implicated genetic variants in an independent British population. A total of 130 asymptomatic controls (CON) and 112 participants clinically diagnosed with ATP comprising 87 individuals with chronic Achilles tendinopathy (TEN) and 25 with Achilles tendon ruptures (RUP) were included. All participants were genotyped for variants within the COL5A1, MIR608, IL-1β, IL-6 and CASP8 genes. Primary findings implicated COL5A1 and CASP8. Three inferred allele combinations constructed from COL5A1 rs12722, rs3196378 and rs71746744 were identified as risk modifiers. The T–C–D combination was associated with increased risk of ATP (P = 0.023) and RUP (P < 0.001), the C–A–I combination was associated with increased risk of ATP (P = 0.011), TEN (P = 0.011) and RUP (P = 0.011) and the C–C–D combination was associated with decreased risk of ATP (P = 0.011) and RUP (P = 0.004). The CASP8 rs3834129 DD genotype was associated with decreased risk of TEN (P = 0.020, odds ratio: 0.45, 95% confidence interval: 0.22–0.90) and the CASP8 I–G (rs3834129–rs1045485) inferred allele combination was associated with increased risk of TEN (P = 0.031). This study further highlights the importance of polymorphisms within COL5A1 and CASP8 in the aetiology of ATP.  相似文献   

7.
This study investigated the evolution of physical and technical performances in the English Premier League (EPL), with special reference to league ranking. Match performance observations (n = 14,700) were collected using a multiple-camera computerised tracking system across seven consecutive EPL seasons (2006–07 to 2012–13). Final league rankings were classified into Tiers: (A) 1st–4th ranking (n = 2519), (B) 5th–8th ranking (n = 2965), (C) 9th–14th ranking (n = 4448) and (D) 15th–20th ranking (n = 4768). Teams in Tier B demonstrated moderate increases in high-intensity running distance while in ball possession from the 2006–07 to 2012–13 season (P < 0.001; effect size [ES]: 0.68), with Tiers A, C and D producing less pronounced increases across the same period (P < 0.005; ES: 0.26, 0.41 and 0.33, respectively). Large increases in sprint distance were observed from the 2006–07 to 2012–13 season for Tier B (P < 0.001; ES: 1.21), while only moderate increases were evident for Tiers A, C and D (P < 0.001; ES: 0.75, 0.97 and 0.84, respectively). Tier B demonstrated large increases in the number of passes performed and received in 2012–13 compared to 2006–07 (P < 0.001; ES: 1.32–1.53) with small-to-moderate increases in Tier A (P < 0.001; ES: 0.30–0.38), Tier C (P < 0.001; ES: 0.46–0.54) and Tier D (P < 0.001; ES: 0.69–0.87). The demarcation line between 4th (bottom of Tier A) and 5th ranking (top of Tier B) in the 2006–07 season was 8 points, but this decreased to just a single point in the 2012–13 season. The data demonstrate that physical and technical performances have evolved more in Tier B than any other Tier in the EPL and could indicate a narrowing of the performance gap between the top two Tiers.  相似文献   

8.
This study examined the effect of carbohydrate mouth rinsing on endurance running performance in women. Fifteen female recreational endurance runners, who used no oral contraceptives, ran two races of 1-h duration on an indoor track (216-m length) at 18:00 h after an 8-h fast with a 7-days interval between races, corresponding to the 3rd-10th day of each premenopausal runner’s menstrual cycle, or any day for the postmenopausal runners. In a double-blind random order, participants rinsed their mouth with 25 ml of either a 6.4% carbohydrate (RCHO) or a placebo solution (RP). No fluid was ingested during exercise. Serum 17β-Εstradiol (P = 0.59) and Progesterone (P = 0.35) did not differ between treatments. There was no difference in 1-hour running performance (RCHO: 10,621.88 ± 205.98 m vs. RP: 10,454.00 ± 206.64 m; t = 1.784, P = 0.096). Furthermore, the mean percentage effect (±99%CI) of RCHO relative to RP, 1.67% (?1.1% to 4.4%), and Cohen’s effect size (d = 0.21) support a trivial outcome of RCHO for total distance covered. In conclusion, carbohydrate mouth rinsing did not improve 60-min track running performance in female recreational runners competing in a low ovarian hormone condition, after an 8-h fast and when no fluid was ingested during exercise.  相似文献   

9.
Acute exercise reduces postprandial triacylglycerol concentrations ([TAG]) in boys and girls; however, it is not known whether between-sex differences exist in response to exercise. Fifteen boys (mean(SD): 11.8(0.4) years) and sixteen girls (12.1(0.7) years) completed two, 2-day conditions. On day 1, participants rested (CON) or completed 10 × 1 min high-intensity interval runs at 100% maximal aerobic speed with 1 min recovery (HIIR). On day 2, participants consumed a standardised breakfast and lunch over a 6.5-h period during which seven capillary blood samples were collected. Based on ratios of the geometric means (95% CI for ratios), fasting [TAG] was 32% lower in boys than girls (?44 to ?18%, ES = 1.31, P < 0.001), and 12% lower after HIIR than CON (?18 to ?5%, ES = 0.42, P = 0.003); the magnitude of reduction was not significantly different between the sexes (8% (ES = 0.36) vs. 15% (ES = 0.47), respectively; P = 0.29). The total area under the [TAG] versus time curve was 27% lower in boys than girls (?40 to ?10%, ES = 1.02, P = 0.005), and 10% lower after HIIR than CON (?16 to ?5%, ES = 0.36, P = 0.001); the magnitude of reduction was similar between the sexes (11% (ES = 0.43) vs. 10% (ES = 0.31), respectively; P = 0.87). The small-moderate reduction in postprandial [TAG] after HIIR was similar between the sexes.  相似文献   

10.
Muscle utilisation in squat exercise depends on technique. The purpose of this study was to compare net joint moments (NJMs) and muscle activation during squats without and with restricted leg dorsiflexion. Experienced men (n = 5) and women (n = 4) performed full squats at 80% one repetition maximum. 3D motion analysis, force platform and (EMG) data were collected. Restricting anterior leg rotation reduced anterior leg (P = 0.001) and posterior thigh (P < 0.001) rotations, resulting in a smaller knee flexion range of motion (P < 0.001). At maximum squat depth, ankle plantar flexor (P < 0.001) and knee extensor (P < 0.001) NJM were higher in unrestricted squats. Hip extensor NJM (P = 0.14) was not different between squat types at maximum squat depth. Vastus lateralis (P > 0.05), vastus medialis (P > 0.05) and rectus femoris (P > 0.05) EMG were not different between squat types. Unrestricted squats have higher ankle plantar flexor and knee extensor NJM than previously reported from jumping and landing. However, ankle plantar flexor and knee extensor NJM are lower in restricted squats than previous studies of jumping and landing. The high NJM in unrestricted squat exercise performed through a full range of motion suggests this squat type would be more effective to stimulate adaptations in the lower extremity musculature than restricted squats.  相似文献   

11.
The purpose of this study was to assess the acute effect of high-intensity interval exercise (HIIE) and moderate-intensity exercise (MIE) on glucose tolerance, insulin sensitivity and fat oxidation in young boys. Eleven boys (8.8 ± 0.8 y) completed three conditions: 1) HIIE; 2) work-matched MIE; and 3) rest (CON) followed by an oral glucose tolerance test (OGTT) to determine glucose tolerance and insulin sensitivity (Cederholm index). Fat oxidation was measured following the OGTT using indirect calorimetry. There was no effect for condition on plasma [glucose] and [insulin] area under the curve (AUC) responses following the OGTT (P > 0.09). However, there was a “trend” for a condition effect for insulin sensitivity with a small increase after HIIE (P = 0.04, ES = 0.28, 9.7%) and MIE (P = 0.07, ES = 0.21, 6.5%) compared to CON. There was an increase in fat oxidation AUC following HIIE (P = 0.008, ES = 0.79, 38.9%) compared to CON, but with no differences between MIE and CON and HIIE and MIE (P > 0.13). In conclusion, 7- to 10-year-old boys may have limited scope to improve insulin sensitivity and glucose tolerance after a single bout of HIIE and MIE. However, fat oxidation is augmented after HIIE but not MIE.  相似文献   

12.
We examined the influence of caffeine supplementation on cognitive performance and perceptual responses in female team-game players taking low-dose monophasic oral contraceptives of the same hormonal composition. Ten females (24 ± 4 years; 59.7 ± 3.5 kg body mass; 2–6 training sessions per week) took part in a randomised, double-blind, placebo-controlled crossover-design trial. A 90-min intermittent treadmill-running protocol was completed 60 min following ingestion of a capsule containing either 6 mg ? kg?1 anhydrous caffeine or artificial sweetener (placebo). Perceptual responses (ratings of perceived exertion (RPE), feeling scale (FS), felt arousal scale (FAS)), mood (profile of mood states (POMS)) and cognitive performance (Stroop test, choice reaction time (CRT)) were completed before, during and after the exercise protocol, as well as after ~12 h post exercise. Caffeine ingestion significantly enhanced the ratings of pleasure (P = 0.008) and arousal (P = 0.002) during the exercise protocol, as well as increased vigour (POMS; P = 0.007), while there was a tendency for reduced fatigue (POMS; P = 0.068). Caffeine ingestion showed a tendency to decrease RPE (P = 0.068) and improve reaction times in the Stroop (P = 0.072) and CRT (P = 0.087) tests. Caffeine supplementation showed a positive effect on perceptual parameters by increasing vigour and a tendency to decrease fatigue during intermittent running activity in female games players taking low-dose monophasic oral contraceptive steroids (OCS).  相似文献   

13.
The objective was to investigate the relationship between Catechol-O-methyltransferase (COMT) rs4680 and serotonin-transporter-linked polymorphic region (5-HTTLPR) genotypes with concussion history and personality traits. Rugby players (“all levels”: n = 303), from high schools (“junior”, n = 137), senior amateur, and professional teams (“senior”, n = 166), completed a self-reported concussion history questionnaire, Cloninger’s Tridimensional Personality Questionnaire, and donated a DNA sample. Participants were allocated into control (non-concussed, n = 140), case (all) (previous suspected or diagnosed concussions, n = 163), or case (diagnosed only) (previous diagnosed concussion, n = 140) groups. COMT rs4680 Val/Val genotypes were over-represented in controls in all levels (P = 0.013, OR:2.00, 95% CI:1.15–3.57) and in juniors (P = 0.003, OR:3.57, 95% CI:1.45–9.09). Junior Val/Val participants displayed increased “anticipatory worry” (P = 0.023). The 5-HTTLPR low expressing group was under-represented in controls when all levels were considered (P = 0.032; OR:2.02, 95% CI:1.05–3.90) and in juniors (P = 0.021; OR:3.36, 95% CI:1.16–9.72). Junior 5-HTTLPR low and intermediate expressing groups displayed decreased “harm avoidance” (P = 0.009), “anticipatory worry” (P = 0.041), and “fear of uncertainty” (P < 0.001). This study provides preliminary indications that personality associated genetic variants can influence concussion in rugby.  相似文献   

14.
The effects of sodium phosphate and caffeine supplementation were assessed on repeated-sprint ability. Using a randomised, double-blind, Latin-square design, 12 female, team-sport players participated in four trials: (1) sodium phosphate and caffeine, (2) sodium phosphate and placebo (for caffeine), (3) caffeine and placebo (for sodium phosphate) and (4) placebo (for sodium phosphate and caffeine), with ~21 days separating each trial. After each trial, participants performed a simulated team-game circuit (4 × 15 min quarters) with 6 × 20-m repeated-sprints performed once before (Set 1), at half-time (Set 2), and after end (Set 3). Total sprint times were faster after sodium phosphate and caffeine supplementation compared with placebo (Set 1: P = 0.003; Set 2: d = ?0.51; Set 3: P < 0.001; overall: P = 0.020), caffeine (Set 3: P = 0.004; overall: P = 0.033) and sodium phosphate (Set 3: d = ?0.67). Furthermore, total sprint times were faster after sodium phosphate supplementation compared with placebo (Set 1: d = ?0.52; Set 3: d = ?0.58). Best sprint results were faster after sodium phosphate and caffeine supplementation compared with placebo (Set 3: P = 0.007, d = ?0.90) and caffeine (Set 3: P = 0.024, d = ?0.73). Best sprint times were also faster after sodium phosphate supplementation compared with placebo (d = ?0.54 to ?0.61 for all sets). Sodium phosphate and combined sodium phosphate and caffeine loading improved repeated-sprint ability.  相似文献   

15.
This study aimed to assess the effects of core stability training on lower limbs’ muscular asymmetries and imbalances in team sport. Twenty footballers were divided into two groups, either core stability or control group. Before each daily practice, core stability group (n = 10) performed a core stability training programme, while control group (n = 10) did a standard warm-up. The effects of the core stability training programme were assessed by performing isokinetic tests and single-leg countermovement jumps. Significant improvement was found for knee extensors peak torque at 3.14 rad · s?1 (14%; P < 0.05), knee flexors peak torque at 1.05 and 3.14 rad · s?1 (19% and 22% with P < 0.01 and P < 0.01, respectively) and peak torque flexors/extensors ratios at 1.05 and 3.14 rad · s?1 (7.7% and 8.5% with P < 0.05 and P < 0.05, respectively) only in the core stability group. The jump tests showed a significant reduction in the strength asymmetries in core stability group (?71.4%; P = 0.02) while a concurrent increase was seen in the control group (33.3%; P < 0.05). This study provides practical evidence in combining core exercises for optimal lower limbs strength balance development in young soccer players.  相似文献   

16.
Abstract

Physiological responses and performance were examined during and after a simulated trampoline competition (STC). Fifteen elite trampoline gymnasts participated, of which eight completed two routines (EX1 and EX2) and a competition final (EX3). Trampoline-specific activities were quantified by video-analysis. Countermovement jump (CMJ) and 20 maximal trampoline jump (20-MTJ) performances were assessed. Heart rate (HR) and quadriceps muscle temperature (Tm) were recorded and venous blood was drawn. A total of 252 ± 16 jumps were performed during the STC. CMJ performance declined (P < 0.05) by 3.8, 5.2 and 4.2% after EX1, EX2 and EX3, respectively, and was 4.8% lower (P < 0.05) than baseline 24 h post-competition. 20-MTJ flight time was ~1% shorter (P < 0.05) for jump 1–10 after EX2 and 24 h post STC. Tm increased (P < 0.05) to ~39°C after the warm-up, but declined (P < 0.05) 1.0 and 0.6ºC before EX2 and EX3, respectively. Peak HR was 95–97% HRmax during EX1-3. Peak blood lactate, plasma K+ and NH3 were 6.5 ± 0.5, 6.0 ± 0.2 mmol · l?1 and 92 ± 10 µmol · l?1, respectively. Plasma CK increased (P < 0.05) by ~50 and 65% 0 and 24 h after STC. In conclusion, a trampoline gymnastic competition includes a high number of repeated explosive and energy demanding jumps, which impairs jump performance during and 24 h post-competition.  相似文献   

17.
This study investigated the effect of hypohydration produced by exercise and sub-optimal rehydration on appetite and energy intake. Ten males lost ~2% body mass through evening exercise in the heat (35°C). Over the next 13 h, participants were re-fed and either rehydrated (RE: water equal to 175% of body mass loss (BML)) or remained hypohydrated (HYPO: 200 ml water), until the following morning. Urine samples, blood samples and subjective feelings were collected pre-exercise, post-exercise and 13 h post-exercise, with an ad libitum breakfast provided 13 h post-exercise. Total BML at 13 h post-exercise was greater during HYPO (2.8 (0.5)%) than RE (0.5 (0.5)%). Energy intake at the ad libitum breakfast was similar between trials (RE: 4237 (1459) kJ; HYPO: 4612 (1487) kJ; P = 0.436), with no difference in energy consumed in foods (P = 0.600) or drinks (P = 0.147). Total water ingestion at the ad libitum breakfast meal was greater during HYPO (1641 (367) ml) than RE (797 (275) ml) (P < 0.001), with this being explained by increased water intake through fluids (P < 0.001). Thirteen hours post-exercise, participants reported greater thirst (P < 0.001) and lower fullness (P < 0.01) during HYPO. Alterations in hydration status produced by exercise are unlikely to influence post-exercise food intake and consequently other aspects of recovery or adaptation.  相似文献   

18.
The aim of this study was to determine the influence of barefoot running on foot-strike patterns, eversion–inversion, running speed and vertical foot rotation in endurance runners. Eighty healthy recreational runners (age = 34.11 ± 12.95 years old, body mass index = 22.56 ± 2.65 kg · m?2) performed trials in shod/unshod running conditions on a treadmill at comfortable and competitive self-selected speeds. Data were collected by systematic observation of lateral and back recordings at 240 Hz. McNemar’s test indicated significant differences between shod/unshod conditions and foot strike at comfortable and competitive speeds (P < 0.001). Speed was related to vertical foot rotation type for shod (P < 0.01) and unshod conditions (P < 0.05). Significant differences were found between shod/unshod conditions in foot rotation at comfortable running speeds (P < 0.001) and competitive running speeds (P < 0.01). No significant difference was found in inversion or eversion (P ≥ 0.05). In conclusion, the results suggest that running kinematics, in terms of foot-strike patterns and vertical foot rotation, differ between shod/unshod conditions, while the inversion or eversion degree remains unchanged.  相似文献   

19.
Downhill backwards walking causes repeated, cyclical loading of the muscle–tendon unit. The effect this type of repeated loading has on the mechanical behaviour of the Achilles tendon is presently unknown. This study aimed to investigate the biomechanical response of the Achilles tendon aponeurosis complex following a downhill backwards walking protocol. Twenty active males (age: 22.3 ± 3.0 years; mass: 74.7 ± 5.6 kg; height: 1.8 ± 0.7 m) performed 60 min of downhill (8.5°), backwards walking on a treadmill at ?0.67 m · s?1. Data were collected before, immediately post, and 24-, 48- and 168-h post-downhill backwards walking. Achilles tendon aponeurosis elongation, strain and stiffness were measured using ultrasonography. Muscle force decreased immediately post-downhill backward walking (P = 0.019). There were increases in Achilles tendon aponeurosis stiffness at 24-h post-downhill backward walking (307 ± 179.6 N · mm?1, P = 0.004), and decreases in Achilles tendon aponeurosis strain during maximum voluntary contraction at 24 (3.8 ± 1.7%, P = 0.008) and 48 h (3.9 ± 1.8%, P = 0.002) post. Repeated cyclical loading of downhill backwards walking affects the behaviour of the muscle–tendon unit, most likely by altering muscle compliance, and these changes result in tendon stiffness increases.  相似文献   

20.
This study investigated the two different time-of-day effect on team-handball-related short-term maximal physical performances. At two different time-of-day, fifteen young female team handball players performed different physical tests: HandGrip (HG) test, Ball-Throwing Velocity (BTV) test, Modified Agility T-test (MAT) and Repeated Shuttle-Sprint and Jump Ability (RSSJA) test. Rating of perceived exertion (RPE) scale was determined following the termination of the last test. Measurements were performed at two separate testing sessions (i.e., in the morning (7:00–8:30 h) and in the early evening (17:00–18:30 h)) in a randomised and counter-balanced setting on non-consecutive days. The results showed that HG (P = 0.0013), BTV (P = 0.0027) and MAT (P < 0.001) performances were better in the evening compared with the morning. During RSSJA, both best and mean sprint times were shorter in the evening compared to the morning (P < 0.001). Moreover, during the latter test, mean jump performance was higher in the evening compared to the morning (P = 0.026). However, there was no morning–evening difference in the best jump performance during RSSJA. Likewise, jump performance decrement was not affected by the time-of-day of testing. On the other hand, RPE fluctuated, with morning nadirs and afternoon/early evening highest values. The findings suggest that in female team handball players, team-handball-related short-term maximal physical performances were better in the afternoon than in the morning.  相似文献   

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