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This paper evaluates a new and adaptive real-time cadence detection algorithm (CDA) for unconstrained sensor placement during walking and running. Conventional correlation procedures, dependent on sensor position and orientation, may alternately detect either steps or strides and consequently suffer from false negatives or positives. To overcome this limitation, the CDA validates correlation peaks as strides using the Sylvester's criterion (SC). This paper compares the CDA with conventional correlation methods.22 volunteers completed 7 different circuits (approx. 140 m) at three gaits-speeds: walking (1.5 m s- 1), running (3.4 m s- 1), and sprinting (5.2 and 5.7 m s- 1), disturbed by various gait-related activities. The algorithm was simultaneously evaluated for 10 different sensor positions. Reference strides were obtained from a foot sensor using a dedicated offline algorithm.The described algorithm resulted in consistent numbers of true positives (85.6-100.0%) and false positives (0.0-2.9%) and showed to be consistently accurate for cadence feedback across all circuits, subjects and sensors (mean ± SD: 98.9 ± 0.2%), compared to conventional cross-correlation (87.3 ± 13.5%), biased (73.0 ± 16.2) and unbiased (82.2 ± 20.6) autocorrelation procedures.This study shows that the SC significantly improves cadence detection, resulting in robust results for various gaits, subjects and sensor positions.

Sarcopenia, the age-associated loss of muscle mass (Narici&Maffulli, 2010) is a main determinant of functional impairment and physical disability in old age. However, the prevalence of sarcopenia amongst fully independent individuals and its reversibility in response to resistive training (RT) are scarcely known. Hence, this study aimed at establishing (i) the prevalence of sarcopenia in fully independent older individuals and (ii) the efficacy of a 12-week RT programme in reversing sarcopenia and its associated muscle weakness. METHODS 26 participants (14 men and 12 women), aged 65-83 yrs, were recruited for this study and underwent 12-week of RT, (3 times/week, 3 sets,14-16 reps), on a leg press machine. Pre- and post-training measurements included: Skeletal Muscle Index (SMI, by bioelectrical impedance); Gait speed (GS) over 4 m; Stair climbing power (SCP); Muscle Architecure of vastus lateralis muscle (pennation angle (Ɵ) and muscle thickness (MT) measured by ultrasonography); 1RM on the leg press. Data were analyzed with descriptive statistics and paired Student’s t-test. RESULTS Before training the prevalence of type I sarcopenia was 61.5% and of type II was 38.5% (classified according to Janssen, 2002). Considering the changes in functional performance, 77% participants (20/26) were responders, while 23% of the participants were non-responders (6 out of 26). For the responders, SMI increased by 2.5% (29.5±4.7 vs 30.3±4.5 %, p<0.001), GS by 5.2% (1.32±0.2 vs 1.39±0.2 ms-1, n.s.), SCP by 7.7% (300.3±111.2 vs 321.8±144.5 W, p=0.04), Ɵ by 8.5% (13.8±3.7 vs 14.9±3.3 deg, p=0.03), MT by 3.5% (1.72±0.4 vs 1.78±0.4 cm, n.s.). 1RM increased by 69% (89.2±59.2 vs 150.8±69.0 kg, p<0.001). 2 participants moved from class II to I sarcopenia and 5 participants from I to a normal SMI . CONCLUSIONS The present findings show that sarcopenia affects >50% of a population of fully independent older individuals (65+ yrs), and that significant improvements in muscle mass, strength

Background: loss of skeletal muscle mass (sarcopenia) is one of the most profound changes affecting the human body with ageing (Narici &Maffulli 2010) as it reduces strength, mobility and ability to dispose of circulating blood-sugar, eventually reducing quality of life of individuals. However there is paucity of data on the prevalence of sarcopenia in non-clinical populations and in particular how this affects mobility and quality of life. Aim: to investigate the association between sarcopenia and variables related to quality of life in a population of medically stable, community-dwelling elderly men and women. Method: 88 participants (40 male and 48 female), age range 64-83 years (mean 72.3 ± 4.6 years), body mass index (BMI) men: 26.5 ±3.7 and women: 24.7±3.5, were recruited for this study and underwent the following measurements: a) Body Composition analysis (by bioelectrical impedance, BIA), b) Gait speed, measured over 4 m, c) Quality of Life (QoL) measured using the Medical Outcomes Survey Short-form General Health Survey (SF- 36) translated and validated in Italian (Apolone and Mosconi, 1998) and, d) Physical Activity level, measured with the IPAQ-short version, (Mannocci et al. 2010). The data were analyzed with descriptive statistics and strength of monotonic relationship between paired data was tested with the Spearman correlation coefficient. Results: BIA Skeletal Muscle Index (SMI) was 34.3±3.2 for men and 30.8±4.9 for women; 45 participants (51%) were classified as sarcopenic and 43 (49%) as non-sarcopenic according to Janssen et al. (2002). SMI significantly correlated with musculoskeletal pain (Rho=-0.245; p<0,05), in particular sarcopenic people reported a more intensive musculoskeletal pain. Instead, no correlation between SMI and physical activity level was found. IPAQ categorical score was low 10% (n=9), moderate 42% (n=37), high 40% (n=16) for the men and low 13% (n=6), moderate 33% (n=16), high 54% (n=26) for the women and IPAQ score was positi

Introduction Several tests are commonly used to evaluate the hamstring and low-back flexibility in health-related physical fitness batteries. They are, in general, referred to the sit-and-reach (SAR) test. The most popular and easy to perform are the V-shape leg position by American College Sport Medicine (1) and that proposed by the Eurofit Battery protocol (2). In this study, the correlation between anthropometric characteristic and the lower back RoM measure was analysed in female university students. Materials and methods A total of 106 female sport science university students (age range 23–19 yr; SD± 1.2 yr) volunteered to the study. The main inclusion criteria were the absence of musculoskeletal injuries and of low back pain. Each participant underwent two different SAR tests performed in two different days of the week. No warm up or specific exercises were performed prior the flexibility performance. Body mass was measured to the nearest 0.5 kg on a beam-balance scale and stature was measured to the nearest 1 cm with a stadiometer. Body Mass Index was calculated and the length between the greater trochanter and the lateral malleolus (with knee in full extension) was measured to define the proportion of lower limbs. The length of the spine (C7-L5) were also measured. All protocol procedures were carried out by the same operator and in the same gym. Results The anthropometric characteristic were for body mass 55.3 ± 5.2 kg and 1.67 ± 0.05 m for height. On average the BMI was 19.8 ± 1.5. The SAR result was 47.2 ± 11.3 cm about V-leg position while the European protocol assessed 11.2 ± 7.6 cm. The coefficient of variation was 0.23 and 0.67, respectively. No significant correlations were found between the anthropometric and ROM. The underweight female performed 50 cm and 14.7 cm for American and European protocol respectively. Discussion These kind of test have a good relation with hamstring flexibility even if do not separate the muscular and joint effects (3); h

The prevalence of overweight and obesity among children and adolescents is rising in the European region with an increase of the onset of risk factors associated with ill health (1). Time spent in sedentary (SED) behaviour and physical activity (PA) have been both associated with adiposity (2, 3). The aim of this study was to investigate the influence of physical activity and sedentary behaviours from childhood (CH) to adolescence (AD). METHODS: The study population consisted of 2828 students aged between 6 and 14 years old (height, 1,45±0,16 m; weight, 39,6±12,7 kg; BMI, 18,3±3,0 kg/m2) and was divided into two groups: CH and AD. Subjects were classified as normal weight (NW), overweight (OW) and obese (OB) according to Cole classification (4). Parents were asked to fill a questionnaire inquiring about time spent in PA, and SED behaviours outside school hours on a weekly basis. The amount of PA was evaluated adding leisure time PA, time spent playing sports and time spent in physically active commutes to and from school. SED activities included TV viewing, playing or working on a computer/playing videogames and any other sedentary activities. A multiple logistic regression analysis, adjusted for sex and age, was used to assess the association between BMI category and PA or SED; significance was set at p<0,05. RESULTS: 79,9% of the cohort was classified as NW, 17,1% as OW and only 3,9% as OB. Overweight and obesity significantly decreased from CH to AD (X2=33,45; p<0,0001). The average amount of PA was 245,5±152,2 min/week and the SED time reached 1739,1±809,7 min/week, both significantly increasing from CH to AD (ANOVA; p<0,0001). PA was not significantly correlated with SED in neither CH nor AD (r=-0,031 and 0,024; respectively). Significant associations, were identified between SED (odds ratio (OR): 1,001; 95%CI: 1,000-1,001; p<0,001) and PA (OR: 0,997, 95%CI: 0,996-0,999; p<0,01) level and obesity. No associations persisted for overweight. DISCUSSION: According