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INTRODUCTION Walking is an automatic motor task and healthy form of physical activity that can be performed at light, moderate or vigorous intensity. There are significant changes in gait across the life span, especially in older adults. In particular, motion patterns deteriorate with age [1], with a decrement of variability, being reported as a potential predictor of falling risk. Gait variability was associated with many factors related to falls, such as strength and balance [2], but less is known about the influence of other physical function components like aerobic fitness and physical activity levels. Principal component analysis (PCA) allows splitting kinematic walking data into a main (regular) and a residual (irregular) pattern of whole-body motion. Walking irregularity can be then quantified by the residual variance (RV), that is, the relative amount of variance in the residual patterns [3]. Hence, the purpose of the current work was to investigate if a relationship exists between gait variability, physical activity levels and oxygen uptake during walking in older women. METHODS Six minutes of treadmill walking performed at 4.5 km/h by a group of old women (n=13, 684 y, BMI 26.42.2 kg/m2) was recorded by a motion analyzer (BTS Spa, Italy). During the trial, oxygen uptake (VO2, ml/kg/min) was measured with a portable spirometer (K4b2, Cosmed Spa, Italy) and subtracted to the standing rate (VO2 SMR). The 3D coordinates of 23 markers of each participant were assembled in a posture matrix P, after shape registration and subtraction of the mean posture, to filter out anthropometric differences between subjects and take into account only the movement patterns. P was submitted to PCA, getting the principal components (PC), each characterized by its proportion of explained variance. Kinematic walking data are highly structured, with two or three PCs typically explaining the vast majority of variance. The first three PCs explained 97.290.46% of the overall varian

INTRODUCTION Many subjective factors can affect energy cost (V’O2max, [7]; maximal strength and flexibility, [3]) and mechanical work (stride frequency, [6]) of walking. To our knowledge, no studies have been conducted to investigate if the level of daily physical activity (PAL) can affect external mechanical work (WEXT) and net energy cost (NetEC) of treadmill walking. The aim of the study was to analyse the relation between NetEC and WEXT with PAL. 2. MATERIALS AND METHODS 20 healthy adults were recruited in the study and were classified as inactive (INACT) and active (ACT) according to the amount of daily moderate and vigorous physical activity (MVPA). Main characteristics are summarized in Table 1. NetEC (obtained from GrossEC– Standing metabolic rate) was analysed with indirect calorimetry (K4b2, Cosmed, Italy) and simultaneously, a kinematic analysis was performed with an optoelectronic system (SMART-E, BTS, Italy) to calculate WEXT during 3 bouts of treadmill walking of 10 min each at 0.97/1.25/1.53 m/s. To assess PAL, subjects wore an activity monitor (Actiheart, CamNtech, UK) for a whole week, inferring time spent in sedentary (SED, <1.5 METs), or moderate to vigorous (MVPA, >3 METs) physical activity. Statistical Analysis: One-way ANOVA was performed to evaluate differences between ACT and INACT. A repeated measure ANOVA (2x3) was used to determine differences between velocities. An ANCOVA analysis was made to find out associations between NetEC and WEXT with PAL. The correlation analysis was performed to investigate relationships between variables. Significance was set at p<0.05. 3. RESULTS When compared with INACT, ACT had a significantly higher amount of MVPA (P<0,0001). No group differences were observed for SED behaviour (Table 2).NetEC increased significantly at all velocities, except for speed from 0.97 to 1.25 m/s. On the contrary, WEXT decreased significantly when velocities grow up, excluding speed from 1.25 to 1.53 m/s (Fig.1-2).No significant a

AIM: Dancesport is increasing its popularity and it becomes to be considered as a real sport. Few studies are available about the physiological strain of dancesport competitions: moreover, recent changes in the official rules make it mandatory to revise our knowledge about the specific physiologic demands during competition. The aim of our study was to evaluate physiological parameters in top-level dancers. METHODS:Twelve competitive dancesport couples (12 Latin-American and 12 Standard dancers) composed the study population. The first testing session was aimed at determining physical and physiological characteristics of athletes in laboratory; the second, at establishing physiological responses during simulated competition on field, involving the measurement of O2 uptake (VO2), heart rate and blood lactate (BL). RESULTS:Male dancers showed a peak-VO2 of 60.9±6.0 and 59.2±7.0 mL/kg/min for Standard and Latin-American dancers, respectively. For females, peak-VO2 was 53.7±5.0 mL/kg/min in Standard and 52.3±5.0 mL/kg/min in Latin-American dancers. During simulated competition, male dancers reached the 75.7±10.6 and 84.2±11.2% of peak-VO2 (P<0.05) for Standard and Latin-American sequence, respectively. For females, no difference was observed (70.8±13.8% in Latin-American and 72.5±12.8% in Standard). Peak-BL during simulated Standard competition was 6.50±2.1 and 6.91±2.6 mM in males and females, respectively, and, for Latin-American sequence, 7.95±2.1 mM in males and 6.04±2.5 mM in females. CONCLUSION:Dancesport can be defined as a sport discipline with an alternate physical activity with medium lasting and high energy-demanding (both aerobic and anaerobic) consecutive phases, separated by short recovery periods. These data must be kept into account while planning specific training programs in sportdancers.

La evidenziata diminuzione nella pratica di giochi di movimento da cortile costituisce una perdita significativa di abitudini motorie che influenza lo stile di vita sedentario dei bambini di oggi. Numerosi studi attestano in loro una diminuzione progressiva nelle abilità motorie dovuta a fattori sia coordinativi che condizionali. Inoltre, il tempo dedicato all’attività ludico-motoria è diminuito e nei momenti di tempo libero stanno aumentando i giochi sedentari a danno di quelli motori. Le cause di questa situazione sono differenti e riteniamo essere : 1) l’avvento dei giochi elettronici, ormai intriganti ed interessanti nel bambino più che i giochi di movimento oltre ad essere meno faticosi; 2) la carenza di spazi sicuri e protetti all’aperto in quanto i vecchi “ cortili” oggi fungono da parcheggio di autovetture. I bambini pertanto vengono indirizzati verso i giochi statici da camera in quanto gli spazi aperti risultano pericolosi; 3) nel sistema scolastico i bambini non sono educati adeguatamente alle attività di movimento e si ritiene che i giochi si debbano utilizzare solo per i momenti di ricreazione.

The aim of this study was to compare different measurement techniques (indirect calorimetry, IC; heart rate monitoring, HR; Actiheart, AH, an activity monitoring system; rates of perceived exertion, RPE) to estimate physical activity intensity (PAI) during water based exercises (WE). Twelve young active women performed five different WE at three different movement frequencies (15 trials) in an indoor swimming pool (Raffaelli et al., 2010). During the trials the subjects were monitored with: a portable metabolic system (K4b2, Cosmed, I), a heart rate monitor (T31, Polar, Fi), the Actiheart (Cambridge Neurotechnology, UK) and the Borg Scale. Each trial lasted 10 min, with a 5 min rest in between; the data recorded at steady state (5 - 9th min) were averaged to obtain mean VO2, HR and AH values. Finally, VO2 was also estimated from HR data using three different HR/VO2 regression equation models (ACSM, 1998; Brown al., 1998; Raffaelli et al., 2010). The values obtained by means of AH, HR and RPE were all significantly related with data of IC (p<0.001); the highest correlations were found between the measured values of VO2 (IC) and the values of VO2 estimated from the three HR/VO2 equations (r>0.8 in all cases). The ANOVA test showed a non significant difference between all predicted and measured VO2 values. When the Bland&Altman analysis was considered, the Actiheart values showed the larger explained variances (95% CI) and the larger standard errors. In conclusion, even if all the analyzed methods are able to detect changes of intensity during WE and are significantly correlated with IC data, the more accurate way to estimate PAI during WE is still based on HR measurements. REFERENCES ACSM (1998) Med Sci Sports Exerc 30: 975-991 Brown al. (1998) Journal of Aging and Physical Activity 6: 248-255 Raffaelli et al. (2010) Eur J Appl Physiol DOI: 10.1007/s00421-010 1419-5

Excess post-exercise oxygen consumption (EPOC) causes an increase in caloric burn during the recovery period, to be considered in relation to energy balance and weight loss. It is not clear whether various modes of aerobic exercise affect EPOC differently. The aim of this study was to evaluate the acute effects of moderate intensity of cycling (CE), treadmill (TE) and arm crank (AE) exercises on EPOC. 6 young moderately active female (age, 24,2±0,8 yr; BMI, 21,5±2,4 kg/m2; RMR, 1288±78,2 kcal/day) participated in the study over a 2-week period. In the first week, subjects filled a Baecke questionnaire of habitual physical activity, undergone a resting metabolic rate (RMR) measurement and a V O2peak at each ergometer was assessed. In the second week, subjects completed one bout of 30 min at 60% of V O2peak (respectively at CE, TE and AE, separated by 48 hours of rest). Before (30 min pre) and after (2 hours post) each exercise bout a RMR measurement was carried out in a sitting position (K4b2, Cosmed, Italy). A repeated measures Anova was used to analyse data. V O2 during exercise and total energy expenditure were significantly higher for TE and CE when compared with AE (TE 1,5±0,2 l/min, 356,8±35 kcal; CE 1,4±0,2 l/min, 344,2±38,6 kcal; AE 0,7±0,1 l/min, 242,3±23,7; p<0,05). QR was significantly lower for TE when compared with CE and AE both during exercise and recovery (exercise: TE 0,81±0,04; CE 0,84±0,07; AE 0,84±0,03; p<0,05). EPOC magnitude was not significantly different for the three exercises (TE 2,9±1,9 l; CE 3,3±2,5 l; AE 1,8±1 l; ns) and accounted between 7% and 11% of total energy expenditure. This study shows that TE can be considered the best weight loss exercise when compared with CE and AE.

Introduction Whole body vibrations (WBV) have been studied as an alternative exercise intervention for enhancing muscle strength and power. Some authors have investigated their influence on the neuromuscular and neuroendocrine system1. Despite the encouraging findings on untrained individuals, it is still not clear whether WBV training may be beneficial for elite athletes. The aim of this work is to compare the effectiveness of similar training programmes, consisting of WBV, traditional resistance exercise with weights or their combination. Methods 18 healthy competitive female athletes (23.84.6 y; 1.660.05 m; 58.87.8 kg) were randomly assigned to 3 treatment groups (V, B and VB). They carried out an 8-weeks periodised conditioning programme, 2 cycles of 3 weeks with 2 training session each, followed by a week of tapering. During training sessions, subjects performed 6 sets of 6 repetitions of dynamic squat: on a vibrating platform (Nemes LX-B/E, SAIR, Italy) (V); with a weight loaded barbell (B); with a weight loaded barbell on a vibrating platform (VB). Vibration frequency was initially set at 25 Hz and was increased of 5 Hz every 2 weeks for both V and VB. Barbell loads were set at 60% and 30% of subject s body mass (BM) for B and VB, respectively, and was increased of about 3% (for VB) and 6% BM (for B) every 2 weeks. Countermovement jump and isometric force tests were carried out before and after the training period. Jumping height and power were estimated by Optojump system (Microgate, Italy). Isometric force was measured by force platforms (Twin Plates, Globus, Italy). They were fixed onto the footplate of a leg press, whose seat was locked so that the subject s knees maintained a 90 deg flexion angle. Proper recovery intervals were respected to avoid fatigue. Following a normality test, non-parametric within groups tests (Wilcoxon) were applied (=0.05). Results Jumping height (mean over 3 trials) and jumping height and power (mean over 15 s of continuous

INTRODUCTION Many subjective factors can affect energy cost (V’O2max, [7]; maximal strength and flexibility, [3]) and mechanical work (stride frequency, [6]) of walking. To our knowledge, no studies have been conducted to investigate if the level of daily physical activity (PAL) can affect external mechanical work (WEXT) and net energy cost (NetEC) of treadmill walking. The aim of the study was to analyse the relation between NetEC and WEXT with PAL. 2. MATERIALS AND METHODS 20 healthy adults were recruited in the study and were classified as inactive (INACT) and active (ACT) according to the amount of daily moderate and vigorous physical activity (MVPA). Main characteristics are summarized in Table 1. NetEC (obtained from GrossEC– Standing metabolic rate) was analysed with indirect calorimetry (K4b2, Cosmed, Italy) and simultaneously, a kinematic analysis was performed with an optoelectronic system (SMART-E, BTS, Italy) to calculate WEXT during 3 bouts of treadmill walking of 10 min each at 0.97/1.25/1.53 m/s. To assess PAL, subjects wore an activity monitor (Actiheart, CamNtech, UK) for a whole week, inferring time spent in sedentary (SED, <1.5 METs), or moderate to vigorous (MVPA, >3 METs) physical activity. Statistical Analysis: One-way ANOVA was performed to evaluate differences between ACT and INACT. A repeated measure ANOVA (2x3) was used to determine differences between velocities. An ANCOVA analysis was made to find out associations between NetEC and WEXT with PAL. The correlation analysis was performed to investigate relationships between variables. Significance was set at p<0.05. 3. RESULTS When compared with INACT, ACT had a significantly higher amount of MVPA (P<0,0001). No group differences were observed for SED behaviour (Table 2).NetEC increased significantly at all velocities, except for speed from 0.97 to 1.25 m/s. On the contrary, WEXT decreased significantly when velocities grow up, excluding speed from 1.25 to 1.53 m/s (Fig.1-2).No significant a

La evidenziata diminuzione nella pratica di giochi di movimento da cortile costituisce una perdita significativa di abitudini motorie che influenza lo stile di vita sedentario dei bambini di oggi. Numerosi studi attestano in loro una diminuzione progressiva nelle abilità motorie dovuta a fattori sia coordinativi che condizionali. Inoltre, il tempo dedicato all’attività ludico-motoria è diminuito e nei momenti di tempo libero stanno aumentando i giochi sedentari a danno di quelli motori. Le cause di questa situazione sono differenti e riteniamo essere : 1) l’avvento dei giochi elettronici, ormai intriganti ed interessanti nel bambino più che i giochi di movimento oltre ad essere meno faticosi; 2) la carenza di spazi sicuri e protetti all’aperto in quanto i vecchi “ cortili” oggi fungono da parcheggio di autovetture. I bambini pertanto vengono indirizzati verso i giochi statici da camera in quanto gli spazi aperti risultano pericolosi; 3) nel sistema scolastico i bambini non sono educati adeguatamente alle attività di movimento e si ritiene che i giochi si debbano utilizzare solo per i momenti di ricreazione.