Testing the performance of an innovative markerless technique for quantitative and qualitative gait analysis

Gait abnormalities such as high stride and step frequency/cadence (SF-stride/second, CAD-step/second), stride variability (SV) and low harmony may increase the risk of injuries and be a sentinel of medical conditions. This research aims to present a new markerless video-based technology for quantitative and qualitative gait analysis. 86 healthy individuals (mead age 32 years) performed a 90 s test on treadmill at self-selected walking speed. We measured SF and CAD by a photoelectric sensors system; then, we calculated average \ub1 standard deviation (SD) and within-subject coefficient of variation (CV) of SF as an index of SV. We also recorded a 60 fps video of the patient. With a custom-designed web-based video analysis software, we performed a spectral analysis of the brightness over time for each pixel of the image, that reinstituted the frequency contents of the videos. The two main frequency contents (F1 and F2) from this analysis should reflect the forcing/dominant variables, i.e., SF and CAD. Then, a harmony index (HI) was calculated, that should reflect the proportion of the pixels of the image that move consistently with F1 or its supraharmonics. The higher the HI value, the less variable the gait. The correspondence SF-F1 and CAD-F2 was evaluated with both paired t-Test and correlation and the relationship between SV and HI with correlation. SF and CAD were not significantly different from and highly correlated with F1 (0.893 \ub1 0.080 Hz vs. 0.895 \ub1 0.084 Hz, p < 0.001, r2 = 0.99) and F2 (1.787 \ub1 0.163 Hz vs. 1.791 \ub1 0.165 Hz, p < 0.001, r2 = 0.97). The SV was 1.84% \ub1 0.66% and it was significantly and moderately correlated with HI (0.082 \ub1 0.028, p < 0.001, r2 = 0.13). The innovative video-based technique of global, markerless gait analysis proposed in our study accurately identifies the main frequency contents and the variability of gait in healthy individuals, thus providing a time-efficient, low-cost means to quantitatively and qualitatively study human locomotion

Gokyo Khumbu/Ama Dablam Trek 2012

In the expedition Gokyo Khumbu/Ama Dablam Trek 2012, we studied the effects of two 12-day training periods performed both at sea level and at high altitude. The main results on adult women have been published in six original articles. In women, high altitude trekking induced CD69 T cell activation and promoted anti-stress effects of the immune responses and the oxidative balance (1). Low-to-moderate exercise training at s.l. improves the regenerative capacity of skeletal muscle and depicted the epigenetic signature of satellite cells. The cell differentiation was favored by increased [Ca2+]i and fusion index (2). On the contrary, the training in hypobaric-hypoxia induced oxidative stress and impaired the regenerative capacity of satellite cells (6). Although training did not significantly modify muscle phenotype , it induced beneficial adaptations of the oxygen transport-utilization systems witnessed by faster VO2 kinetics at exercise onset (3). The two training periods did not influence the postural stability (4). In young adult women, micturition physiological parameters were affected during adaptation to hypoxia; the correlation with SpO2 strongly suggests a role of hypoxia in these changes (5

Handcycling: training effects of a specific dose of upper body endurance training in females

Purpose: This study aims to evaluate a handcycling training protocol based on ACSM guidelines in a well-controlled laboratory setting. Training responses of a specific dose of handcycling training were quantified in a homogeneous female subject population to obtain a more in depth understanding of physiological mechanisms underlying adaptations in upper body training. Methods: 22 female able-bodied participants were randomly divided in a training (T) and control group (C). T received 7-weeks of handcycling training, 3 × 30 min/week at 65 % heart rate reserve (HRR). An incremental handcycling test was used to determine local, exercise-specific adaptations. An incremental cycling test was performed to determine non-exercise-specific central/cardiovascular adaptations. Peak oxygen uptake (peakVO2), heart rate (peakHR) and power output (peakPO) were compared between T and C before and after training. Results: T completed the training sessions at 65 ± 3 % HRR, at increasing power output (59.4 ± 8.2 to 69.5 ± 8.9 W) over the training program. T improved on handcycling peakVO2 (+18.1 %), peakPO (+31.9 %), and peakHR (+4.0 %). No improvements were found in cycling parameters. Conclusion: Handcycling training led to local, exercise-specific improvements in upper body parameters. Results could provide input for the design of effective evidence-based training programs specifically aimed at upper body endurance exercise in females

Circulating microRNAs in sera correlate with soluble biomarkers of immune activation but do not predict mortality in ART treated individuals with HIV-1 infection: A case control study

Introduction: The use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals. Materials and Methods: A set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed. Results: None of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR- 145 correlated with nadir CD4+ T cell count. Discussion: No associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection

Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study

Ristola M. on työryhmien DAD Study Grp ; Royal Free Hosp Clin Cohort ; INSIGHT Study Grp ; SMART Study Grp ; ESPRIT Study Grp jäsen.Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with >= 3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1: 393 chance of developing CKD in the next 5 y in the low risk group (risk score = 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria. Conclusions Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.Peer reviewe

What is the work-load during training sessions in rugby union?

There is a great interest in coaches and fitness trainers to define the physical demands of training, in order to optimize the training process, to evaluate the players\u2019 performance and provide suitable recovery time and nutrition. The determination of training load can be particularly challenging in Rugby Union, a team sport played by 15 players of highly variable build, that is characterized by short, high intensity efforts (struggle, impacts, sprinting) and longer, low intensity activities (standing still, walking, jogging).Our study aimed at applying a heart rate based approach to measure absolute and relative workloads in two typologies of training, typically used in rugby union: team session (TS) and unit training (UT).Methods15 forwards (FW) and 15 backs (BK) from Venezia Mestre Rugby (elite Italian senior championship) undertook one incremental test to exhaustion on the treadmill to determine individual VO2max, heart rate (HR) at max and HR/VO2 relationship. Furthermore, within the following month, HR was continuously monitored during 12 training sessions (6 TS and 6 UT).For each training session, we determined absolute (Kcal*kg-1*min-1) and relative intensity (%HRmax, %VO2max,). Mean and standard deviation were calculated in FW and BK for TS and UT sessions and compared by t test (p< 0.05).Results & DiscussionThe athletes were 24\ub13 years old, a 12\ub13 years playing experience and a VO2max of 47\ub15 ml*kg-1*min-1. FW and BK weight and height were: 108\ub18 and 92\ub112 Kg; 187\ub11 and 181\ub11 cm respectively. Workload data are reported in the table. Team session training (TS) Unit training (UT) min %HRmax %VO2max Kcal*kg-1*min-1 min %HRmax %VO2max Kcal*kg-1*min-1FW 59\ub112 72\ub18 58\ub112 0.13\ub10.03 73\ub17\ua7 67\ub16\ua7 52\ub111\ua7 0.12\ub1 0.03\ua7BK 59\ub112 74\ub16* 59\ub19 0.14\ub10.02* 71\ub17\ua7 73\ub14* 58\ub18* 0.14\ub1 0.02** and \ua7 indicate, respectively, a significant difference vs FW and vs TS.ConclusionOur study successfully determined absolute and relative workload during specific training sessions in rugby union players. For BK, absolute and relative workload was similar for the two training modes and higher compared to FW. For FW, TS was performed at a higher absolute and relative intensity compared to UT. In this group of senior players of a national level, the overall workload of both TS and UT was within the moderate intensity domain

Effect of a medium-term high fat diet on muscle oxidative metabolism in healthy males.

Effect of a medium-term high fat diet on muscle oxidative metabolism in healthy males. Gabriela De Roia, Silvia Pogliaghi Faculty of Motor Sciences, University of Verona, Italy PURPOSE: The study tested the hypothesis that a high fat diet (HFD) enhances oxidative metabolism, by augmenting the muscle capacity to extract oxygen. METHOD: 23 healthy males (28\ub15 yrs, 53\ub16 ml*kg-1*min-1) consumed either (#12) a 10-day normocaloric HFD (55, 30, 15% of the total calories from fat, carbohydrate and protein) or (#11) continued their habitual diet (control subjects, C). Before and after the diet, oxidative metabolism was tested non-invasively during an incremental cycling exercise and 3 repetitions of a square-wave exercise of moderate intensity (80% of the first ventilatory threshold). Cardio-respiratory variables were measured breath by breath. Muscle oxygen extraction was measured, at the vastus lateralis, by multiple distance, intensity modulated, near infrared spectroscopy. Maximal (VO2max, muscle oxygen extraction (HHbmax)) and kinetics parameters were calculated at the lung (\uf074p, TDp and mean response time (MRTp) of the primary component) and at the muscle levels (\uf074m, TDm, MRTm). Means and standard deviations were calculated and compared by t test and Bonferroni correction (p<0.05). RESULTS: HFD and C groups were not different at baseline. No changes were detected in C. After the diet, antropometric values remained unchanged (74\ub19 Kg, 1,8\ub10,1 cm, 11\ub14 % of body fat). While VO2max was unaffected, HHbmax was significantly higher after the HFD (37\ub19 vs 41\ub110). During metabolic transitions, at the lungs, \uf074p and MRTp were significantly shorter after HFD (21\ub16 vs 19\ub16 s; 108\ub124 vs 96\ub126 s), with an unchanged TDp (22 \ub1 4 s). Also at muscle level, MRTm was significantly lower after the HFD (18\ub13 vs 17\ub12 s) despite non significant changes in \uf074m (9\ub14 vs 8\ub15s) and TDm (9\ub13 vs 9\ub13). CONCLUTIONS: As a result of HFD, maximal muscle oxygen extraction was significantly increased, yet insufficiently so to affect VO2max. The speed of adaptation of muscle oxidative metabolism, during exercises of moderate intensity (known to be limited primarily by metabolic inertia), was also significantly enhanced by HFD, as evidenced both at the lung and at the muscle levels. Therefore, our data support the hypothesis that a medium-term high fat diet (HFD) enhances oxidative metabolism, in young healthy males, by augmenting the muscle capacity to extract oxygen (peripheral factor). The study was supported by Enervit, Italy