Salivary and serum irisin in healthy adults before and after exercise.

Irisin is an exercise-induced cytokine mainly secreted by myocytes. Circulating level of irisin can increase in response to acute exercise, promoting pleiotropic effects on health. Generally, irisin is evaluated in blood, however, its collection is invasive. Saliva sample would not have any risk associated with blood collection and would represent a less invasive method for irisin detection. Until now, there are only a few studies that have analyzed irisin levels in saliva. In the present research, five healthy male adults performed an incremental exercise until exhaustion on cycle ergometer. Serum and saliva samples were collected before exercise and 15min, 24h and 48h after reaching the exhaustion. Irisin was detected by ELISA assay. Serum and salivary irisin levels increased from baseline to 24h post exercise and reverted to basal levels after 48h of rest. A significant rise of both serum and salivary irisin level at 24h (p≤0.05) compared to baseline levels was found. Furthermore, a significant correlation between irisin percentage change in serum and saliva from baseline to 24h post exercise was detected (r=0.92, p<0.05). Despite the relatively limited sample, this research suggests that collecting saliva samples might represent a valid and less invasive method to detect irisin level changes induced by exercise.

The Relationship between ACE, ACTN3 and MCT1 Genetic Polymorphisms and Athletic Performance in Elite Rugby Union Players: A Preliminary Study.

Athletic performance is influenced by many factors such as the environment, diet, training and endurance or speed in physical effort and by genetic predisposition. Just a few studies have analyzed the impact of genotypes on physical performance in rugby. The aim of this study was to verify the modulation of genetic influence on rugby-specific physical performance. Twenty-seven elite rugby union players were involved in the study during the in-season phase. Molecular genotyping was performed for: angiotensin-converting enzyme (ACE rs4646994), alfa-actinin-3 (ACTN3 rs1815739) and monocarboxylate transporter 1 (MCT1 rs1049434) and their variants. Lean mass index (from skinfolds), lower-limb explosive power (countermovement jump), agility (505), speed (20 m), maximal aerobic power (Yo-yo intermittent recovery test level 1) and repeated sprint ability (12 × 20 m) were evaluated. In our rugby union players ACE and ACTN3 variants did not show any influence on athletic performance. MCT1 analysis showed that TT-variant players had the highest peak vertical power (p = 0.037) while the ones with the AA genotype were the fastest in both agility and sprint tests (p = 0.006 and p = 0.012, respectively). Considering the T-dominant model, the AA genotype remains the fastest in both tests (agility: p = 0.013, speed: p = 0.017). Only the MCT1 rs1049434 A allele seems to be advantageous for elite rugby union players, particularly when power and speed are required.

Genetics and Sport Injuries: New Perspectives for Athletic Excellence in an Italian Court of Rugby Union Players.

Several genes are involved in sport performance, especially in injuries incidence. The aim of this study was to investigate the association of ACE, ACTN3, COL1A1, and MCT1 genotypes and injuries in rugby players in order to find a genotype/phenotype correlation and provide useful information improving athletic performance. One-hundred male professional and semiprofessional rugby players were selected. Analysis was performed genotyping the genes ACE, ACTN3, COL1A1, and MCT1 as candidate gene of interest involved in athletic performance. A control group of non-athletic Italian male participants was analyzed to compare the results. We found statistical significance of MCT1 rs1049434 AA for total injuries (χ2 = 0.115; p = 0.003) and bone injuries (χ2 = 0.603; p = 0.007) in the rugby athlete population. No statistical significance was found between injury incidence and ACE, ACTN3, COL1A1 genotypes. The MCT1 AA genotype is associated with the incidence of total and bone injuries in the rugby player population. Although environmental factors such as lifestyle, diet, training, and stress can influence athletic performance, our data demonstrated the importance of genetic study in sport aimed at developing personalized training and achieving the best possible athletic excellence.

Prediction and Analysis of Tokyo Olympic Games Swimming Results: Impact of the COVID-19 Pandemic on Swimmers' Performance.

Due to the COVID-19 pandemic in the 2019-2020 season, swimming competitions and training have been limited leading to a setback in performances. The study analyzed if, during the subsequent season, swimmers' have been able to regain the lost performance. Swimming time trends were analyzed comparing Tokyo with Rio Olympics and with mathematically predicted results. The gap between the gold medalist and the last finalist, and the differences between men and women have also been considered. Swimming competition results of females and males, in 100 m and 200 m Freestyle and Backstroke, were collected from the Olympics' official website. Results showed that at Tokyo Olympics almost all swimmers' times improved as compared to Rio's. Analysis of performance trends highlighted that performance progression does not proceed in a linear fashion and that is best predicted by more recent results. Women's progression was higher than men's and the gap between the first and last finalist constantly decreased, except for the Tokyo Olympics. In conclusion, the unprecedented Tokyo Olympic Games and qualification year seems not to have disrupted all Olympic swimmers' performance, suggesting that stakeholders support and athlete's coping ability might safeguard the subsistence of performance.

Correlations Between Physical Activity Level, Quality of Life, and Cognitive Performance in Elderly Individuals Engaging in Multi-Year Dance Activities.

INTRODUCTION: It is well-acknowledged that cognitive and physical decline associated with aging can be prevented or reduced with the engagement in regular physical activity (PA). Dance activities combine cardiovascular, cognitive, and coordinative demands, providing a popular leisure PA among elderly. This study examined the correlations between quality of life (QoL), cognitive and physical performance, and PA level in older adults who participated in at least 10 years of amateur ballroom dancing.
Methods: The study was designed as an observational study. A sample of 20 (10 men; age range: 65 to 80 years; BMI: 26.3 ± 3.0 kg/m²) amateur senior dancers were compared with a sample of 18 (8 men; age range: 65 to 75 years; BMI: 25.5 ± 2.4 kg/m²) non-sedentary individuals (control group) following an adapted PA program. Quality of life and cognitive functioning assessment tools were administered: 36 Health Status Survey (SF-36v2), Montreal Cognitive Assessment (MoCA), and Cognitive Reserve Index questionnaire (CRIq). Physical performance was measured with their preferred walking speed (PWS), and level of moderate to vigorous physical activity (MVPA) was evaluated using a multi-sensor activity monitor.
Results: Participants presented a good SF-36v2 physical component and a very good mental com- ponent summary, a total MoCA score within the limits, and an average total CRIq score. Their PWS and daily MVPA were high. Differences neither in the three questionnaires nor in PWS and PA level were observed between groups. A significant, moderate, and positive correlation was found between PWS and SF-36v2 physical component summary score.
Conclusion: Ballroom dancing seems to allow elderly individuals to maintain good cognitive and physical abilities, QoL, an acceptable normal cognitive reserve, notable physical performance, and PA level to the same extent as an adapted PA program. Both types of PA seem to be able to contrast the mental and physical decline associated with aging.

Physiological and exertional responses of partner dance in elderly.

BACKGROUND: In order to verify if partner dance is an appropriate physical activity (PA) for elderly, to promote and maintain healthy fitness level, physiological and exertional responses during ballroom and smooth dance in elderly were examined. METHODS: Twenty healthy amateur dancers (10 men and 10 women, age 72.0±5.9 years, BMI 25.5±4.2 kg/m2) with multiyear dancing experience performed 3 different kinds of ball (choosing between Mazurka, Viennese Waltz and Polka or Slow Waltz, Tango and Foxtrot), each lasting 3 minutes, with a 3-minute recovery between consecutive balls. Cardiorespiratory data were continuously recorded with a portable metabolimeter (K5, Cosmed Srl., Rome, Italy) in order to assess metabolic equivalent task (METs) of each ball. The Borg Category-Ratio anchored at the number 10 (CR10 Scale) was used to assess perceived effort (RPE) at the end of each ball. RESULTS: There were no gender differences in METs and RPE. Also, no differences in RPE were observed between balls. The mean METs for ballroom dance were: Tango 4.3±1.1, Slow Waltz 4.5±1.1 and Foxtrot 4.8±1.4 METs, respectively; the mean METs for smooth dance were: Mazurka 5.3±0.9, Viennese Waltz 5.8±0.8 and Polka 5.9±1 METs, respectively. Polka elicited significantly higher METs values than Tango (P<0.0007) and Slow Waltz (P<0.0017); Viennese Waltz elicited significantly higher METs values than Tango (P<0.0016), too. CONCLUSIONS: In general, ballroom and smooth dance demanded moderate to vigorous PA intensity levels (according to the specific classification for elderly). Therefore, all studied dance styles met the suggested intensity of the current guidelines for elderly and thus may serve as a legitimate form of PA for elderly.

Fatigue Induced by Repeated Changes of Direction in Élite Female Football (Soccer) Players: Impact on Lower Limb Biomechanics and Implications for ACL Injury Prevention.

BACKGROUND: The etiology of Anterior Cruciate Ligament (ACL) injury in women football results from the interaction of several extrinsic and intrinsic risk factors. Extrinsic factors change dynamically, also due to fatigue. However, existing biomechanical findings concerning the impact of fatigue on the risk of ACL injuries remains inconsistent. We hypothesized that fatigue induced by acute workload in short and intense game periods, might in either of two ways: by pushing lower limbs mechanics toward a pattern close to injury mechanism, or alternatively by inducing opposed protective compensatory adjustments. AIM: In this study, we aimed at assessing the extent to which fatigue impact on joints kinematics and kinetics while performing repeated changes of direction (CoDs) in the light of the ACL risk factors. METHODS: This was an observational, cross-sectional associative study. Twenty female players (age: 20-31 years, 1st-2nd Italian division) performed a continuous shuttle run test (5-m) involving repeated 180°-CoDs until exhaustion. During the whole test, 3D kinematics and ground reaction forces were used to compute lower limb joints angles and internal moments. Measures of exercise internal load were: peak post-exercise blood lactate concentration, heart rate (HR) and perceived exertion. Continuous linear correlations between kinematics/kinetics waveforms (during the ground contact phase of the pivoting limb) and the number of consecutive CoD were computed during the exercise using a Statistical Parametric Mapping (SPM) approach. RESULTS: The test lasted 153 ± 72 s, with a rate of 14 ± 2 CoDs/min. Participants reached 95% of maximum HR and a peak lactate concentration of 11.2 ± 2.8 mmol/L. Exercise duration was inversely related to lactate concentration (r = -0.517, p < 0.01), while neither%HR max nor [La-] b nor RPE were correlated with test duration before exhaustion (p > 0.05). Alterations in lower limb kinematics were found in 100%, and in lower limb kinetics in 85% of the players. The most common kinematic pattern was a concurrent progressive reduction in hip and knee flexion angle at initial contact (10 players); 5 of them also showed a significantly more adducted hip. Knee extension moment decreased in 8, knee valgus moment increased in 5 players. A subset of participants showed a drift of pivoting limb kinematics that matches the known ACL injury mechanism; other players displayed less definite or even opposed behaviors. DISCUSSION: Players exhibited different strategies to cope with repeated CoDs, ranging from protective to potentially dangerous behaviors. While the latter was not a univocal effect, it reinforces the importance of individual biomechanical assessment when coping with fatigue.

Horse-Riding Competitions Pre and Post COVID-19: Effect of Anxiety, sRPE and HR on Performance in Eventing.

The aim of the present study was to quantify the impact of training restrictions, due to COVID-19 sanitary emergency, on physical and emotional strain of horse-riding Eventing competitions before and after eight weeks of lockdown. Performance was assessed by the penalty points attained, anxiety by the Competitive State Anxiety Inventory-2, strain by the Rating of Perceived Exertion (RPE) method. Moreover, Heart Rate was continuously monitored for fifty-four female national level Eventing horse-riders. Lockdown decreased performance outcome of horse-riders in Eventing competitions up to six weeks, with the Dressage test being the most affected discipline. Performance in Dressage was strongly related to both anxiety and session-RPE. After lockdown, Show-Jumping and Cross-Country courses were shorter allowing RPE to remain stable, session-RPE to significantly decline and cardiovascular strain not to exceed pre-lockdown values. In conclusion, emotional stress in Dressage and workload in Cross-Country should be carefully managed by equestrian Eventing stakeholders when planning training and competitions after a period of lockdown. Moreover, sRPE appears to offer a practical method of monitoring riders load during training and competition and could also be of use for home-based training during any future sport activities restrictions.

School self-efficacy is affected by gender and motor skills: findings from an Italian study.

BACKGROUND: Perceived school self-efficacy (SE) is an important variable in students' activities as it affects their motivation and learning. Further, self-efficacy might represent a good predictor of performance, persistence and perseverance. Motor skills and other physical health determinants are extensively debated and linked to cognitive function in children of developmental age. However, inconclusive evidence supports a definitive relationship between perceived school SE and motor skills among schoolchildren. We conducted a cross-sectional study on 6-11-year-old schoolchildren to evaluate the extent by which perceived school SE and physical health determinants were related. METHODS: A SE questionnaire and motor performance battery tests were administered to primary school pupils recruited from 154 sampled schools of northwest Italy. Perceived SE at school was assessed via 12 items from the Caprara's questionnaire. Motor performance scores were obtained from motor skill tests: 4 × 10 m shuttle run test, SRT; standing broad jump, SBJ; six-minute walking test, 6MWT. RESULTS: A total of 3,962 children (M = 2,019; F = 1943) were studied and 68% were normal weight. Overall, a 58% of the sample perceived a high SE, while, as to gender differences, a greater percentage of females perceived high levels of school SE with respect to any other level (χ2 = 38.93, p < 0.0001). Results from multinomial logistic regression analysis revealed that: (i) females perceived higher SE compared to males; (ii) children who performed better in SRT and 6MWT showed higher levels of perceived school SE; (iii) no significant effect was registered for the body weight. Alternative strategies are encouraged to enhance SE through physical education: structured interventions might enhance both complex motor skills and high-order cognitive skills, like SE, in young children.

High Intensity Interval Training Does Not Have Compensatory Effects on Physical Activity Levels in Older Adults.

BACKGROUND: Exercise has beneficial effects on older adults, but controversy surrounds the purported "compensatory effects" that training may have on total daily physical activity and energy expenditure in the elderly. We wanted to determine whether 8 weeks of high-intensity interval training (HIIT) induced such effects on physical activity and energy expenditure in healthy, active older adult men. METHODS: Twenty-four healthy elderly male volunteers were randomized to two groups. The experimental group performed HIIT (7 × 2 min cycling repetitions, 3 d/w); the control group performed continuous moderate-intensity training (20-30 min cycling, 3 d/w). Physical activity and energy expenditure were measured with a multisensor activity monitor SenseWear Armband Mini. RESULTS: During HIIT, significant changes were observed in moderate and vigorous physical activity, average daily metabolic equivalents (METs), physical activity level, and activity energy expenditure (p < 0.05) but not in total energy expenditure. Sleep and sedentary time, and levels of light physical activity remained constant during the training period. CONCLUSIONS: The findings suggest that HIIT induced no compensatory effect: HIIT does not adversely affect lifestyle, as it does not reduce daily energy expenditure and/or increase sedentary time.

Kinematic traits of an elite paralympic karateka: a case report.

Karate is a martial art that includes striking, kicking and punching techniques, and requires high levels of functional skills. Karate counts millions of practitioners worldwide and it is also spreading in Paralympic competitions: there is a need for accurate categories definition for disabled athletes. The aim of the current study was to present kinematic data of an elite Paralympic karateka, in comparison with able-bodied athletes, to promote a better classification within the discipline, based on objective evaluations of physical impairments. A male black belt Paralympic karateka (age: 36 years; body weight: 75.5 kg; height: 173 cm) with lower limbs impairments was evaluated. He performed a standardized sequence of movements (kata) from Shotokan karate. Joints and center-of-mass kinematics were collected with an optoelectronic motion capture system and compared with those obtained in two groups of able-bodied (Masters and Practitioners) athletes from a previous study. The sequence performed by the karateka lasted longer than in both able-bodied groups. Center of mass velocity and acceleration lowered in comparison with Masters. Knees range of movement and peak angular velocity were similar to Practitioners but lower than Masters. We concluded that physical impairments negatively affected the function of lower limbs in the Paralympic athlete, as fundamental skills in karate elite performance (dynamic balance control and joint angular velocity) were lower.

Kinematic effects of repeated turns while running.

In team sports, non-contact ACL and MCL injuries occur during abrupt changes of direction, like turns or cutting manoeuvres. Fatigue affects dynamic neuromuscular control and increases knee injury risk. This study analysed how lower limb joints and centre-of-mass kinematics are affected throughout a high-intensity running protocol involving repeated 180°-turns. Twenty young men (18-23 years, BMI: 20.8-24.4 kg m-2) completed a 5-m shuttle running trial lasting 5 min at an average speed of 75% of their maximum aerobic speed. During the test, cardio-metabolic parameters were obtained, together with joints and centre-of-mass kinematics, using a motion capture system. Kinematic data were compared between the first and the last minute of exercise. Perceived exercise intensity ranged from "hard" to "maximum exertion" and post-exercise lactate concentration ranged from 5.4 to 15.5 mM. The repetition of 180°-turns induced a substantial reduction of hip (-60%, p < .001, large effect) and knee flexion (-40%, p = .003, medium-to-large effect), and an increase of hip adduction and internal rotation (+25-30%, p < .05, medium-to-large effect). Since such movements are factors increasing the likelihood of non-contact knee injuries, we concluded that the prolonged repetition of turns may expose participants to increased risk of ligament failure. Prevention programmes should include discipline-specific neuromuscular training especially in late practices.

Correction: Six minute walk distance and reference values in healthy Italian children: A cross-sectional study.

[This corrects the article DOI: 10.1371/journal.pone.0205792.].

Six minute walk distance and reference values in healthy Italian children: A cross-sectional study.

The 6-minute walking test (6MWT) is a simple assessment tool to evaluate exercise capacity. The result of the test is the distance that a subject can walk at a constant and normal pace within 6 minutes (6MWD) and reflects the aerobic/fitness performance related to walking function. Use of 6MWT has been relevant to assess exercise tolerance either in healthy children or in patients with, heart, lung and metabolic diseases. Our aim was to find 6MWT reference values in healthy Italian children. The 6MWT was performed in 5614 children aged 6-11 years recruited from primary Italian schools. Age related reference percentiles of the covered distance were gender-modeled. A linear and quadratic regression model was used to predict 6MWT performance. Males walked longer distances than females, respectively 598.8±83.9 m vs 592.1±77.6 m (p = 0.0016). According to the regression analysis, 6MWD was positively related to age, gender and height, while it was negatively related to body weight [(6MWD = -160.16 + 93.35× age (years) -4.05× age2 (years) +7.34× gender (m) +2.12× weight (kg) -2.50× height (cm)]. Reference values were established for the 6MWT in healthy children. The age related 6MWD percentiles provided a useful tool in the assessment of capacity in 6-11 year children, in fact they may be helpful to evaluate the effect of a given treatment or rehabilitation program and represent a feasible measure as to prevention within the primary school context. It was found a substantial difference from other countries for 6mwd values. In our study, factors such as age, weight and height were relevant for the prediction of 6MWD, similarly to other studies. Therefore, these variables should be taken into account in context of exercise performance.

Influence of energy cost and physical fitness on the preferred walking speed and gait variability in elderly women.

Typically gait speed decreases and gait variability increases in elderly. The aim of this study was to define the influence of energy cost of walking on gait speed and of health-related physical fitness on gait variability. Thirty healthy young and older women were recruited in the study. Energy cost of walking (NetCW) was analyzed with indirect calorimetry while a kinematic analysis was performed with an optoelectronic system to calculate gait variability (GV) during treadmill walking at different speeds. Gait speed was defined as the preferred walking speed (PWS) of the subject and health related physical fitness (HRPF) comprised body fat, strength, flexibility, and cardiorespiratory fitness. In healthy elderly women, the coefficient of variation of step width was found to be a better indicator of GV than stride time, stride length and double support coefficients of variation. GV was not affected by age allowing a high PWS. Furthermore, significant associations, adjusted for age, body mass index and number of falls, were identified neither between NetCW and the PWS, nor between HRPF and GV; only a significant association was found between hand-grip strength and gait stability. Findings highlighted the importance to evaluate hand-grip strength as an indicator of gait efficiency.

Study of the association between gait variability and physical activity.

BACKGROUND: Gait variability can be considered an indirect measure of gait stability, in particular regarding temporal or spatial variability assessment. Physical activity, such as walking, is advised for the elderly and can be improved by gait stability. The aim of this study was to investigate the associations between gait stability and physical activity in women of different age ranges. METHODS: Forty-two healthy women of different age ranges (18-40 yrs. and 65-75 yrs.) were recruited in the study. To assess physical activity, the subjects wore a multi-sensor activity monitor for a whole week, inferring the time spent in moderate to vigorous physical activity (MVPA). MVPA were analysed in bouts of at least 10 subsequent minutes (MVPAbouts) and in overall minutes (MVPAtot). A kinematic analysis was performed with an optoelectronic system to calculate gait variability - expressed as standard deviation (SD) and coefficient of variability (CV) of step width, stride length, stance and swing time (during treadmill walking at different speeds). RESULTS: Elderly women, with high walking speed (5 km/h), and moderate step width variability (CV = 8-27%), met the recommended levels of physical activity (MVPAtot and MVPAbouts). Furthermore, gait variability, adjusted for age and number of falls, was significantly and negatively associated with MVPAtot only at 3.5 km/h, and with MVPAbouts only at 4 km/h. CONCLUSIONS: In a population of healthy elderly women, gait variability was significantly and negatively associated with the level of physical activity. Healthy elderly women, with moderate gait variability (step width variability), and high preferred walking speed, seem to be able to meet the recommended levels of physical activity.

Dynamic balance in elite karateka.

In karate, balance control represents a key performance determinant. With the hypothesis that high-level athletes display advanced balance abilities, the purpose of the current study was to quantitatively investigate the motor strategies adopted by elite and non-elite karateka to maintain balance control in competition. The execution of traditional karate techniques (kihon) in two groups of elite Masters (n = 6, 31 ± 19 years) and non-elite Practitioners (n = 4, 25 ± 9 years) was compared assessing body center of mass (CoM) kinematics and other relevant parameters like step width and angular joint behavior. In the considered kihon sequence, normalized average CoM height was 8% lower (p < 0.05), while CoM displacement in the horizontal direction was significantly higher in Masters than in Practitioners (2.5 vs. 1.9 m, p < 0.05), as well as CoM average velocity and rms acceleration (p < 0.05). Step width was higher in Masters in more than half of the sequence steps (p < 0.05). Results suggest that elite karateka showed a refined dynamic balance control, obtained through the increase of the base of support and different maneuvers of lower limbs. The proposed method could be used to objectively detect talented karateka, to measure proficiency level and to assess training effectiveness.

Testing and Training of the Eggbeater Kick Movement in Water Polo: Applicability of a New Method.

In water polo, many of the technical actions and the contacts with the opponent take place in quasi-vertical floating position using 2 types of lower limb actions: the eggbeater kick is used most often in fighting and passing and the breaststroke kick in jumping and throwing. The aim of this study was to identify a new system to evaluate and to train the eggbeater kick movement and to verify its applicability. Twenty amateur players and 22 elite players participated in the study. A jacket, homemade and easy to make, allowing the application of an overload submerged in water but not hindering breathing or mobility, was used. Standard anthropometry and a test consisting of different trials of the eggbeater kick action until exhaustion with an increasing overload (5, 7.5, 10, 12.5, 15, and 17.5 kg) were collected. Time to exhaustion and the overload estimated maximum value (OEMV) at second 2 were determined for each load. Body weight, height, and lower limb muscle performance of the elite and nonelite players were significantly different from each other (p ≤ 0.05). The effectiveness of the different measured variables in both subgroups and that of the OEMV was evaluated with receiver operating characteristic (ROC) curve analysis. Areas under the ROC curve for the different overloads were 0.72 (0.53-0.92) for 5 kg, 0.80 (0.68-0.90) for 7.5 kg, 0.87 (0.77-0.91) for 10 kg, and 0.88 (0.84-0.92) for 12.5 kg overload. Our results show that the test is sensitive enough and therefore can be used to plan and control training and injury recovery.

Effect of Leg Dominance on The Center-of-Mass Kinematics During an Inside-of-the-Foot Kick in Amateur Soccer Players.

Soccer kicking kinematics has received wide interest in literature. However, while the instep-kick has been broadly studied, only few researchers investigated the inside-of-the-foot kick, which is one of the most frequently performed techniques during games. In particular, little knowledge is available about differences in kinematics when kicking with the preferred and non-preferred leg. A motion analysis system recorded the three-dimensional coordinates of reflective markers placed upon the body of nine amateur soccer players (23.0 ± 2.1 years, BMI 22.2 ± 2.6 kg/m2), who performed 30 pass-kicks each, 15 with the preferred and 15 with the non-preferred leg. We investigated skill kinematics while maintaining a perspective on the complete picture of movement, looking for laterality related differences. The main focus was laid on: anatomical angles, contribution of upper limbs in kick biomechanics, kinematics of the body Center of Mass (CoM), which describes the whole body movement and is related to balance and stability. When kicking with the preferred leg, CoM displacement during the ground-support phase was 13% higher (p<0.001), normalized CoM height was 1.3% lower (p<0.001) and CoM velocity 10% higher (p<0.01); foot and shank velocities were about 5% higher (p<0.01); arms were more abducted (p<0.01); shoulders were rotated more towards the target (p<0.01, 6° mean orientation difference). We concluded that differences in motor control between preferred and non-preferred leg kicks exist, particularly in the movement velocity and upper body kinematics. Coaches can use these results to provide effective instructions to players in the learning process, moving their focus on kicking speed and upper body behavior.

Assessment of physical activity in anorexia nervosa and treatment outcome.

PURPOSE: The aim of this study was to compare objective and subjective assessments of physical activity (PA) in patients with anorexia nervosa and its effect on treatment outcome. METHODS: Both Actiheart (AH) and International Physical Activity Questionnaire (IPAQ) were used to assess PA in 52 female patients with anorexia nervosa during the first week of inpatient treatment. RESULTS: No correspondence between PA estimated by IPAQ, which had a tendency to underestimate PA, and that measured using AH emerged. However, a significant association was found between the change in Eating Disorder Examination global score at the end of the treatment and light PA measured by AH (beta = -0.12, t = -2.44, P = 0.019), but not that estimated by IPAQ. CONCLUSIONS: PA in patients with anorexia nervosa is underestimated by subjective assessment when compared with objective measurement. Only time spent in light PA, assessed objectively with AH, showed a negative association with improvement in eating disorder psychopathology.