Sport Sciences for Health

Background Several studies report martial arts as a good model for investigating neuroendocrine responses to competitive fighting. However, little is known on the metabolic responses elicited by elite athletes during fighting. In particular, the metabolic picture in elite athletes of martial arts is little known. Aim In the present study, our aim was to investigate the acute effects of a session of karate practice on the glucose-insulin system. Subjects and methods Ten healthy individuals (6M/4F; BMI: 22.1 ± 0.7 kg/m2; 21.9 ± 1.1 years, mean ± SE) who practice karate in national or international competitions were enrolled. All participants completed two experimental trials in a randomised-crossover fashion. A basal blood sample was collected from each athlete to assess plasma glucose, insulin, cortisol, testosterone and catecholamines, before karate training session. In two separate days, another blood sample was collected from each participants after 3 min of real fighting (kumite) and 3 min of ritualized simulation of combat (kata). Results In both trials, plasma glucose resulted to be higher at the end the of performance compared to the basal (p < 0.001 after kumite and p < 0.02 after kata). In contrast, insulin was similar in the basal and after physical activity in the two trials. Catecholamines were higher after kata and kumite sessions with respect to the basal values (p < 0.04) and, in particular, epinephrine post-kumite values were much greater than those measured after kata. Conclusions Our results indicate that unlike performances of karate (kumite and kata) elicit different plasma glucose increases. In particular, we found that glucose and epinephrine concentrations increased more after kumite than after kata.

Lower limbs strength capacity in female soccer players is poorly addressed. The aim of this study was to evaluate explosive strength in 7-on-7 (7FP) and 11-on-11 (11FP) female players and its possible changes at 3 different checkpoints of the competitive season. Thirteen 11FP of mean age 22.0 years) and twenty-six 7FP (of mean age 23.6 years) were enrolled. Vertical jump capacity was determined by means of squat jump (SJ) and counter movement jump (CMJ) tests in 3 different periods (September 2005, December 2005, April 2006). No significant differences were observed in SJ elevation or CMJ elevation between the two groups at any time point, and there were no significant changes over time. However, 7FPs tended to have higher explosive performance during SJ compared to 11FPs, and they had a significantly lower elastic recoil index at all three evaluations. This may be due to the characteristics of 7-on-7 soccer, in which the neuromuscular and explosive strength demands are higher than those of 11-on-11 soccer. Such requirements, though increasing muscular explosive performance, also increase the rigidity of the lower limb extensor apparatus.

Sedentary habits and obesity are important problems in public health. The main objective of this study has been to increase motivation level and physical activity practice in overweight and obese patients, through a counseling intervention made from primary care physicians (MMG). The counseling model has been taken from the program PACE (Patient-centered Assessment and Counseling for Exercise and Nutrition). In the period May-April 2002–2003, 145 patients, with a BMI27, underwent a physical activity counseling administered by 10 primary care physicians (MMG). The main measures of outcome were the change of physical activity level and the state of change score and their related improvements; secondary measures: BMI and abdominal circumference. The median follow-up was 7 months. 103 of 145 (71%) agreed to the project; afterwards their motivation level and physical activity increased. BMI and abdominal circumference were reduced. There were no differences between subjects about studied features (sex, age, instruction, work, health). The counseling, following PACEs model, positively influenced the increase of physical activity and motivational level correlated in the patients who participated in the study project. It is necessary to do further studies to evaluate the real efficacy and to understand how this problem influences public health.

The aim of this study is to chart the hypoxic ventilatory decline experienced by climbers exposed to hypoxic stimulus with and without 7 days of acclimatisation to intermittent altitude increases of 4400 to 6960 m. Our results revealed that hypoxic ventilatory depression was present during day 1 of hypoxia and decreased thereafter, returning to control values by day 7. These results indicate that the hypoxic ventilatory response, which is mediated by carotid body chemoreceptors, depends on the pattern and intensity of hypoxia exposure. Chronic intermittent hypoxia could facilitate this recovery, yielding faster returns to ventilatory baseline levels.

Strengthening of abdominal muscles is often used in athletic training and in clinical rehabilitation of subjects with low back pain. Traditionally, it is performed by isometric or concentric abdominal contractions in supine position. Recently, the AB Slider has been introduced as a device to train abdominal muscles in quadrupedic position. The aim of this study was to assess the muscle activity and the type of contraction of the rectus abdominis while performing an exercise with the AB Slider and to compare it to a crunch exercise (CE). Sixteen subjects were trained to correctly perform both exercises. Muscle activity of the rectus abdominis was assessed using surface electromyography, and a stereophotogrammetric system Elite was used for the kinematic analysis. During exercise on the AB Slider, knee extension was 51.3°±9.1° (mean±SD) and the distance between the pelvis and the xiphoid process always increased. During CE, rectus abdominis activity was 73.4%±23.5% of the maximal voluntary (MVC) and during the AB Slider exercise it was 96.2%±23.0% of MVC (p=0.011, Wilcoxon’s test). During the exercise with AB Slider, there was greater activation of the rectus abdominis muscle than during CE. Kinematic analysis indicated that the activity occurs in eccentric conditions. The AB Slider seems to be a good device for strengthening the abdominal muscles.

Available on http://link.springer.com/article/10.1007%2Fs11332-010-0090-x The potency of exercise as a nonphotic time cue compared to the solar cycle in influencing entrainment (organism synchronization within the 24-h period) has yet to be defined. Above the Arctic Circle during winter the sun remains below the horizon for several weeks and during summer remains above the horizon for several weeks. The goal of the present study was to investigate the effects related to exercising time on the circadian structure under conditions of lack of daylight and continuous daylight. The experiments were carried out at 70° North, above the Arctic Circle. Ten healthy females (age 24±5 years) were divided into two groups: an exercise and a control group. The subjects in the exercise group performed the same exercise routine at two different times of day (0900 and 1800 hours) both in January (twilight period) and in May (continuous daylight period). Continuous heart rate data were collected and analysed by the cosinor method. The acrophase values were significantly modified in the exercise group during evening exercise in January showing a delay compared with morning exercise and compared with the control group (3 h and 1.5 h, respectively), while in May this effect was not seen. The results indicate that in continuous daylight, the potency of exercise in modulating the circadian phase seems to be suppressed. However, these findings need to be verified in a larger poulation. Key wordsHeart rate circadian rhythm-Arctic Circle-Exercise-Synchronizer-Phase shift

Lupin proteins allow the preparation of some innovative protein-rich food products, e.g., steaks chunks, cutlets, gyros. With the objective of evaluating the acceptability of these foods in sport nutrition, they were provided to 34 healthy competitive track and field athletes (mean age 25±5, 17 males and 17 females), to be taken before training or a competitive event. Athletes were asked to fill in 3 different questionnaires, reporting possible problems/negative symptoms impacting on acceptability: questionnaire 1 had to be filled in 1 h after food intake, questionnaire 2 immediately after training/competition (i.e., 3–5 h after food intake) and questionnaire 3 on the day after. All 34 participating athletes indicated good satisfaction with the food products, which were generally well accepted. In addition, most of the athletes gave positive reports in terms of sense of satiety, sense of energy and desire to exercise. Therefore, lupin proteins may provide a useful, well accepted approach to pre-exercise nutrition in competitive athletes.

After ACL reconstruction, accelerated rehabilitation allows professional soccer players to return to official matches within 4–6 months of surgery, but in many cases accelerated rehabilitation is impossible. This retrospective study investigated the variables that affect the time to return to competition of professional soccer players after ACL reconstruction. Between October and December 2002, a questionnaire designed for this study was administered to the players competing in the Italian First Division (Series A) who previously reported an ACL reconstruction. Among 479 players surveyed, we identified 38 cases of arthroscopic ACL reconstruction (8%). The mean time to return to competition was 232±135 days from surgery (range, 76–791). In 12 cases (31.6%; group A), there was an isolated ACL rupture and these players returned to competition within 163±44 days after surgery (range, 76–231). Twenty cases were associated with one or more lesions (52.6%; group B), and these players returned to competition within 203±56 days after surgery (range, 146–329). Six cases reported complications after surgery or during rehabilitation (infections, swelling; 15.8%; group C) and returned to competition within 456±203 days after surgery (range, 233–791; p<0.001 compared to groups A and B). In this study, a fast (<4 months) return to competition was achieved only in three cases of isolated ACL rupture (8%). Accelerated rehabilitation (<6 months) seems to be possible only in cases of isolated ACL reconstruction or when only the medial meniscus is involved as an associated lesion. The time to return to competition after ACL reconstruction was independent of the surgical technique used and must be considered the consequence of the complexity of the injury to the knee.

Stretching is usually part of warm-up routines in many sports, but it affects the subsequent muscle force; therefore, it could negatively influence post-activation potentiation (PAP), one of the warm-up’s main effects. The aim of this study was to evaluate the acute effects of passive stretching on PAP and fibre conduction velocity (CV). Seven subjects underwent 2 experimental sessions, control (C) and stretching (S), each consisting of 2 series (7 min resting) of 3 maximal voluntary contractions (MVC) of biceps brachii (5 s isometric contraction, 10 s recovery). During the resting phase of the S session, the biceps brachii was passively stretched (5×45 s stretches, 15 s recovery). Root mean square (RMS), mean frequency (MF) and CV were calculated from electromyography. Peak torque (pT) and half-contraction time (1/2CT) were measured and normalised by the arm muscular area (pTn). After C, pTn increased and 1/2CT decreased (p<0.05); moreover, MF and CV increased (p<0.05). After S, 1/2CT increased (p<0.05) and RMS decreased (p<0.05). Passive stretching could blunt the effects of PAP, presumably due to mechanical and neuromuscular changes. The observed changes in CV suggest a possible decrease in Ca2+ sensitivity in contractile proteins. Therefore, the use of passive stretching in warm-up routines remains questionable.

Energy drinks have gained popularity among athletes. The purpose of this study was to determine the acute effects of Phantom and Dragon energy drinks on endurance performance. For this reason 12 female athlete students of Tehran University (age 22±0.63 years, height 162.1±5.8 cm, weight 56.91±6.79 kg) volunteered and performed three sessions on a Bruce treadmill test four days apart from each other. In each session, in a randomised, placebo-controlled, counterbalanced and double-blind design 6 ml/kg body weight of Phantom, Dragon or placebo was consumed 40 min before an exercise test. Using a 3×3 repeated measures analysis of variance and Least Significant Difference (LSD), a significant increase in VO2max time to exhaustion and a decrease in post-test rating of perceived exertion was found for Phantom and Dragon vs. placebo (p<0.05). No significant difference was observed in pre-test hear rate for three drinks (p>0.05). Post-test hear rate increased significantly for Dragon vs. Phantom and placebo (p<0.05). In conclusion, two commercially available energy drinks had ergogenic effects on endurance performance.

Six young obese females (20.5±1.22 years; BMI=34.5±4.3 kg/m2) participated in a resistance exercise (RE) protocol (12 exercises, 4 sets × 15 repetitions at 60% of 1RM), an aerobic exercise (AE) protocol (3 sets × 10 min ergometer cycling at 60% of maximal heart rate with 5 min of rest between sets), and a control session. Blood samples were collected before, and immediately after and 10 h after exercise. All protocols were done in follicular phase of the menstrual cycle. ANOVA (3×3) with repeated measure on exercise (3 levels) and time (3 levels) factors was used to determine the effects of exercise protocol, time and exercise protocol by blood sampling time interaction, triglycerides, HDL-cholesterol, LDL-cholesterol, and glucose concentrations. Immediately and 10 h after AE, serum leptin was significantly lower (p<0.05). Serum insulin after AE was lower than after RE and control sessions (p<0.05). Furthermore, no significant differences were found in serum leptin and insulin between RE and control sessions immediately after and 10 h after exercise. Blood glucose, triglycerides, total cholesterol, HDL-cholesterol and LDL-cholesterol were unchanged in both exercise protocols. In conclusion, AE resulted in a serum leptin reduction and suppressed the circadian rhythm of serum insulin when sampled immediately and 10 h after exercise; instread, RE did not result in serum leptin or insulin changes.

The purpose of this study was to determine the effect of sprint exercise and a detraining period on lipid peroxidation (malondialdehyde, MDA) and response of antioxidant system (ferric reducing ability of plasma (FRAP), uric acid, bilirubin and total protein). Forty-two male rats were divided randomly into two groups: sprint group (experimental) (n=24) and control group (n=18, without any training programme). The experimental group trained for 12 weeks, 3 times per week, with given intensities. Five trained rats experienced the detraining, so the effects of detraining were also studied (from the 8th to 12th weeks). Data were analysed using a two-way repeated ANOVA. A significant difference between the two groups was observed for MDA (p=0.022), FRAP (p=0.005) and bilirubin (p=0.002) but for total protein and uric acid no significant change occurred. In the experimental group, a significant difference was found through various assessments for MDA (p=0.001), FRAP (p=0.001), bilirubin (p=0.008) and uric acid (p=0.012). It can be concluded that this protocol of sprint exercise training causes adaptation in the antioxidant system and lipid peroxidation, but by detraining these results will be reversed.

The aim of the paper is to investigate whether rotational vestibulo-ocular and visuo-vestibulo-ocular reflexes may undergo different adaptive gain changes depending on specific athletic motor skills required by the different specialities of figure skating. Twenty-five right-handed athletes from the Italian National Figure Skating Team were investigated, divided into three groups according to their discipline: 8 dancers, 13 singles and 4 pairs. Rotational vestibulo-ocular and visuo-vestibuloocular reflexes were recorded by electrooculography as slow phases of per-rotatory nystagmus during 0.10-Hz sinusoidal stimulation, respectively, in the darkness and in the light. Gain was reduced only in dancers whereas it was normal in singles and pairs. A clearcut clockwise directional preponderance was revealed only in dancers. The results confirm that, also from a vestibular point of view, singles and dancers look different, with pairs as an intermediate pattern. Furthermore, it has been shown that the human rotational vestibulo-ocular system is capable of asymmetric adaptation. Alterations in rotational vestibulo-ocular parameters observed in figure skaters result from vestibular habituation, but these kind of adaptations depend on the athletic tasks specific for each discipline, and they provide evidence for interdependent mechanisms for control of clockwise and counterclockwise oculomotor control at least in the low-frequency stimulation domain.

Available on http://link.springer.com/article/10.1007/s11332-009-0074-x A pilot study was conducted to describe the reaction to lack of daylight and different training times of circadian rhythms and sleep in a subject arriving in Alta (Northern Norway) from Milan (Italy) in the darkness period. Monitoring sessions by heart rate (HR) monitor and actigraph were performed after four conditions: MS1, no training in Italy; MS2, no training in Alta (lack of daylight); MS3, evening training in Alta; and MS4, morning training in Alta. Midline Estimating Statistic Of Rhythm (MESOR) for activity was lower in MS2 than in MS1, MS3 and MS4, and decreased progressively for HR. Acrophases were advanced in MS2 and MS4 compared to MS1 and MS3 for both activity and HR. Sleep Efficiency was higher in MS2, MS3 and MS4 compared to MS1, coinciding with low values in the Mean Activity Score and Movement and Fragmentation Index. It could be seen that lack of daylight induced a decrease of the activity state in the subject, advancing the acrophase and leading to increased sleep. After the exercise sessions the activity state of the subject increased and the circadian structure was influenced according to the time at which the training was performed.

In ice hockey, players produce high velocities by skating and game actions are typically characterized by sudden accelerations and brisk decelerations. Thus, the vestibular system is particularly stressed. The aims of this study were to evaluate sensorial organization and head stabilization control of ice hockey players in order to investigate if this kind of activity induces specific sensorimotor adaptation. We studied 8 elite hockey players, 8 amateur players and 10 healthy controls. Three tests were performed: (1) sensory organization test (SOT) to evaluate sensorial organization in maintaining steady stance in quiet standing; (2) head stabilization stance test (H-STAN) to evaluate head-to-trunk stabilization during quiet steady stance; and (3) stepping test (STEP) to evaluate skills in maintaining the head stable with respect to the trunk during walking in place. In SOT, elite players had a greather visual component and reduced vestibular component. In H-STAN test, elites, when standing on foam, presented head less stable than trunk. In STEP test, with respect to normal subjects and amateurs the head of elites was less stable in the sagittal plane with eyes open and more stable in the frontal plane with eyes closed.

Muscular dystrophies (MD), such as Duchenne’s MD (DMD), appear in childhood and progressively lead to respiratory and/or heart failure. Exercise-based therapy may be helpful, but the cardiac and autonomic adaptations to sport activities are poorly studied in MD patients. Heart rate (HR) was measured in 30 players (all males, 28±6 [m±SD] years) with different forms of MD (divided into 2 groups according to pathology severity): (a) before, (b) during and (c) immediately after a wheelchair hockey match. In addition, HR variability (HRV) indexes RMSSD, SD1, LF, HF and LF/HF ratio were measured before and during the game in a subgroup of 9 DMD athletes. A sinus tachycardia was found in all MD athletes before the game (114±13 bpm in DMD, 113±18 bpm in other muscular dystrophies, OMD). In both DMD and OMD groups HR increased significantly from pre-game to game and decreased during recovery. During the game, HR was higher in the OMD compared to the DMD group. The subgroup of DMD athletes evidenced an almost normal parasympathetic withdrawal and altered sympathetic adaptations to exercise. Sinus tachycardia affects MD patients independently from MD form. However, the residual autonomic modulation allows the athletes to adapt to the energetic demands of wheelchair hockey.

The aim of this study was to evaluate the fitness level of Italian male recruits with (volunteers) and without (novices) previous fire-fighting experience. Strength (handgrip; 1RM bench-press), power (counter movement jump (CMJ)), velocity (20 m) and endurance (with and without self-contained breathing apparatus (SCBA)) performances of 29 volunteer (age: 22±3 years; BMI: 23±2) and 51 novice (age 30±5 years; BMI 25±2) fire-fighting recruits were compared (p<0.05). Volunteers showed better performances (p<0.01) for 1RM (80.5±16.5 kg), CMJ (31.4±4.8 cm) and 20 m (3.1±0.2 s) than novices (1RM=68.3±10.5 kg; CMJ=28.0±4.5 cm; 20 m=3.2±0.2 s). No difference emerged for handgrip (481.7±71.4 N) and VO2max with (42.9±5.2 ml/kg/min) and without (54.7±6.2 ml/kg/min) SCBA. Wearing the SCBA, 3% of volunteers and 16% of novices failed to complete the endurance test. Considering that fire fighters perform their job wearing SCBA, it could be advisable to test the fitness level of recruits in this condition.

ObjectiveThe purpose of this investigation was to analyse the effect of sub-maximal acute exercise at different intensities on plasma adiponectin and insulin concentrations in trained and untrained subjects. MethodsSeven trained (TR) and eight untrained (UTR) subjects participated in this study. Subjects performed two submaximal cycling exercises of 20 min each: moderate and heavy. The intensity of the exercises was respectively at 60% and 80% of maximal oxygen consumption ($ \dot V $ \dot V O2max). Blood samples were obtained before, at the end, and after 30, 60 and 90 min of recovery. ResultsAdiponectin concentrations were unchanged after both exercises and during recovery in TR and UTR. Insulin concentrations were significantly lowered (p<0.05 and p<0.01) at the end and during recovery in both protocols and groups. The comparison between groups indicated that TR presented lower control adiponectin and insulin concentrations than UTR during the moderate and the heavy exercise: −51.62%, p<0.05 and −43.33%, p<0.05, respectively for adiponectin and −35.29%, p<0.05 and −35.11%, p<0.05, respectively for insulin. Rest adiponectin levels during the heavy exercise were significantly related to $ \dot V $ \dot V O2max (r=−0.761, p=0.028) and insulin (r=−0.805, p=0.015) in TR. ConclusionsOur results suggested that (1) 20 min of acute aerobic exercises does not stimulate the production of adiponectin during the 90-min recovery in TR and UTR; (2) it appears that adiponectin is not associated with insulin modifications and (3) handball athletes showed significantly lower resting adiponectin and insulin response with respect to untrained subjects. This result is probably due to the increased level of receptor expression induced by training.

Fifteen male high school students (12.5±0.5 years) voluntarily participated in this study. They carried backpacks with 0 (as a control group), 8, 10.5 and 13% of their body weights on a treadmill at 1.1 m/s for 15 min. Their systolic (SBP) and diastolic (DBP) blood pressure was measured by a digital blood pressure meter, and heart rate (HR), minute ventilation (MV) and respiratory frequency (RF) by a Gas Analyzer System, in 3 positions: rest, exercise (15 min walking) and recovery (3 min after walking). The results indicated that the SBP and MV during and 3 min after carrying backpacks 10.5 and 13% of body weight were significantly higher than under 0 and 8% body weight load conditions. The DBP increased significantly only at the 13% body weight load condition, after 15 min of walking. The weight of school backpacks for high school students can be recommended as 8% of their body weight, because carrying 8% body weight load did not significantly change cardio-respiratory parameters.

Impairment of insulin sensitivity of glucose metabolism, a prominent feature of type 1 diabetes (DM), is also well documented in adolescence and obesity. Overweight is frequently present during adolescence in females. Spurt in growth is significantly reduced during puberty in females with type 1 DM, while it is normal in males. In this study we assessed the effect of the coexistence of type 1 DM, adolescence, overweight, and their possible interference with growth. Moreover, we evaluated whether dietetic control associated with physical exercise improved insulin sensitivity in adolescence. The study enrolled 11 female adolescents and young adults (aged 18.50.6 years), affected by type 1 DM for 8.30.9 years, who were overweight (BMI, 27.30.8 kg/m2) and receiving conventional insulin therapy (0.780.10 U/kg day). We used the euglycemic hyperinsulinemic clamp technique coupled to [2H2]glucose and [13C]leucine infusion. The results show a striking increase in insulin resistance of glucose metabolism: the suppression of endogenous glucose production (EGP) was 59% in comparison to 90%–100% recorded by others at similar insulin levels in subjects at different periods of life. Insulin resistance in type 1 DM overweight adolescents was also present on protein metabolism: the postabsorptive plasma leucine (146.910.1 M) and the endogenous leucine flux (ELF, 88.84.5 mol/kg min) were higher than in healthy controls. The suppression of ELF during hyperinsulinemia was defective in diabetic adolescents (27%, p2). In conclusion, overweight female adolescents with type 1 DM have an impaired insulin action on glucose and protein metabolism. Physical exercise and correct dietary regimen positively influence insulin sensitivity. The present preliminary data are relevant for an improved control of glucose homeostasis and a normal growth in adolescence.

The objective of the present study was to evaluate the influence of a programme of training with cerebral stimulation by auditory stimuli on motor learning in the practice of judo. Twenty adolescents of 12–14 years of age were selected and were divided into an Experimental Group (EG) and a Control Group (CG), the EG realising a programme of 36 sessions of judo training of 45 min duration, parallel to a programme of training with cerebral stimulation by auditory stimuli of 35 min duration. The CG realised only the judo programme with the same number of sessions of the same duration. The pre- and post-programme data revealed that the EG, which used both the programme of judo training and the programme of training with cerebral stimulation by auditory stimuli, was significantly superior to the CG (p≤0.05) in relation to performance in learning and memorisation. It is concluded that the results described here are substantial regarding the interactivity between a programme of training with cerebral stimulation, and motor learning and memorisation.

This preliminary study examined the influence of various obstacle heights on the walkway in the timed “Up & Go” (TUG) test on test performance and reliability. Seventeen healthy young men participated in the original TUG test and in the TUG test with an obstacle (TUGO). In TUGO tests, subjects stood up from a chair, walked 5 m on a path that required stepping over an obstacle (0, 3, 5, 10 and 17 cm in height), turned 180°, returned to the chair stepping over the obstacle again and sat down. They were instructed to move as fast as possible. The following parameters were measured; total time required to complete the test, time needed to walk to the obstacle or return, time for turn, single support time pre- and post-stepping over the obstacle (pre- and post-single support times), and distances between each single support foot and the obstacle (pre- and post-single support distances). The total time required for TUGO tests showed very high intra-class correlation coefficients (0.96–0.99) and had significant relationships to that of the TUG test and all gait property parameters regarding time. The results of ANOVA showed that the total time required was significantly shorter with obstacle heights from 0 to 10 cm than it was at the 17 cm height. Turn time, pre-single support time and post-single support distance were longer with obstacle heights over 5 cm as compared to the 0 cm height. Post-single support time was significantly longer at the 17 cm height than at the other heights. Reliability of the TUGO test was very high. The total time required was significantly longer at the 17 cm obstacle height. Even at the relatively low 5 cm obstacle height, turn time, pre-single support time and post-single support distance were longer.

This study aimed to clarify the effect of gender and lateral dominance on grip muscle power. Subjects included healthy young males and females (15 men aged 22.1±0.7 years and 15 women aged 22.4±1.0 years) who were right-hand dominant. Grip muscle power (peak power) was measured in the dominant and non-dominant hands with six different loads ranging from 20% to 70% of maximum voluntary contraction (MVC). The grip muscle power was significantly larger in males than in females and in the dominant hand than in the non-dominant hand. In short, lateral dominance was confirmed. The grip muscle power values increased with increasing loads, and decreased after reaching a maximal value at about 50% MVC in both genders. In contrast, peak velocity decreased with increasing loads. The grip muscle power ratio of the dominant hand to the non-dominant hand was significantly larger in females in all loads. In conclusion, although grip muscle power is superior in males and in the dominant hand, the lateral dominance is more marked in females.

The aim of this study was to observe the effects of a concurrent physical training programme (PTFC) on the muscle strength and body composition of adults. The sample was composed of 54 men, non-athletes, who were split into two groups: the experimental group (EG, n=42, 45±8.46 years of age) and the control group (CG, n=12, 47.17±7.41 years of age). Body composition was assessed by dual-energy X-ray absorptiometry (DEXA) and muscle strength was assessed by testing the repetition maximum (1 RM). The PTFC was composed of race training sessions in the Fatmax intensity zone and strength training. The training sessions were conducted three times a week for 40 min each over a period of 24 weeks. Statistical analysis of the data consisted of a descriptive and inferential analysis: Shapiro-Wilk (normality) and multiple comparisons (ANOVA 2×2). For this study, p<0.05 indicated statistical significance. Significant increases in 1RMs (p=0.001) and 1RMa (p=0.000) were found when comparing the post-test to the intra-EG values. The inter-group analysis revealed an increase in muscle strength in the 1RMa post-test (p=0.005) in favour of the EG group. Importantly, no significant changes in body composition were observed between the groups.

It is a well known fact that in many sport activities, a technical gesture is more effective and easier to perform in a situation of balance. Short-term balance training (BT) seems to be effective for rapidly improving muscular strength and for reducing imbalances between corresponding limbs. Moreover, reducing imbalances between corresponding limbs may be useful for the prevention of injuries. The aim of the present study was to investigate the link between balance and strength in young soccer players. The experiment was carried out on 133 young male soccer players (age: 18.2±1.9). The Libra Fixed Point (LPF)-Libra Closed Eye (LB) balance tests as well as the Counter Movement Jump (CMJ-CMJMono) tests were significantly (p<0.05) correlated (r=0.43 and r=0.63, respectively; p<0.01). Significant correlations (p<0.05) were found between the balance LPF and CMJ (r=−0.36, p<0.01), between LB and CMJ (R=−0.22, p<0.05), between LPF and CMJMono (r=−0.48, p<0.01) and between LB and CMJMono tests (r=−0.42, p<0.01). These results may have interesting implications for the effects of BT.