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Introduction: Master athletes are examples of successful aging. It is not clear whether it is the competitive-oriented training or just the amount of total regular exercise that reduces the age-related decline in physiological functions. We aimed to compare health-related parameters in competitive (C) and physically active older adults (A) that performed the same weekly physical activity (PA) amount. Methods: Seventeen C and 17 A were matched for age (8 and 9 male participants under and over 70 years old respectively, for both groups) and weekly PA amount (GPAQ). Body composition, leg and arm maximal strength, balance and reaction time were measured; moreover, leg and arm exercise efficiency, estimated VO2max, and VO2/HR relationships were evaluated. Perception of life and sleep quality was also assessed through specific questionnaires (SF-36 and PSQI). The effect of group (C vs. A), age (U70 vs. O70) and their interaction was examined through a Two-Way ANOVA test. Results: C dedicated more time to vigorous PA compared to A (p = 0.03), while less to moderate daily work (p < 0.01) and active commuting (p = 0.06). C exhibited better body composition (all p < 0.05), higher leg maximal strength (p < 0.05) and a trend for elevated arm strength (p = 0.06). Reaction time, leg and arm cycling efficiency were similar in the two groups (all p > 0.05), while balance reduced in A O70. Estimated VO2max was higher for C in leg cycling (p = 0.05) and remained constant across ages (all p > 0.05). VO2/HR relationship, life and sleep quality did not differ for groups and ages. Conclusions: Regular physical exercise of about 6,000 METs/week seems to have a beneficial effect on health-related parameters, both in non-structured and competitive PA, when compared to sedentary behaviour. However, the older adults engaged in competitive training exhibit further advantages: better body composition, higher arm and leg muscle strength, and higher leg VO2max. This study highlights the importance of encouraging active lifestyles for maintaining long-term health, high levels of life quality perception and reducing age-related decline. However, vigorous training suitability needs to be verified by a team of PA specialists. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the effect of performing hypoxic exercise at the same heart rate (HR) or work rate (WR) as normoxic exercise on post-exercise autonomic and cardiovascular responses., Methods: Thirteen men performed three interval-type exercise sessions (5 × 5-min; 1-min recovery): normoxic exercise at 80% of the WR at the first ventilatory threshold (N), hypoxic exercise (FiO 2  = 14.2%) at the same WR as N (H-WR) and hypoxic exercise at the same HR as N (H-HR). Autonomic and cardiovascular assessments were conducted before and after exercise, both at rest and during active squat-stand manoeuvres (SS)., Results: Compared to N, H-WR elicited a higher HR response (≈ 83% vs ≈ 75%HRmax, p < 0.001) and H-HR a reduced exercise WR (- 21.1 ± 9.3%, p < 0.001). Cardiac parasympathetic indices were reduced 15 min after exercise and recovered within 60 min in N and H-HR, but not after H-WR (p < 0.05). H-WR altered cardiac baroreflex sensitivity (cBRS) both at rest and during SS (specifically in the control of blood pressure fall during standing phases) in the first 60 min after the exercise bout (p < 0.05). Post-exercise hypotension (PEH) did not occur in H-HR (p > 0.05) but lasted longer in H-WR than in N (p < 0.05)., Conclusions: Moderate HR-matched hypoxic exercise mimicked post-exercise autonomic responses of normoxic exercise without resulting in significant PEH. This may relate to the reduced WR and the limited associated mechanical/metabolic strain. Conversely, WR-matched hypoxic exercise impacted upon post-exercise autonomic and cardiovascular responses, delaying cardiac autonomic recovery, temporarily decreasing cBRS and evoking prolonged PEH.

Introduction: Very little is known about talent development and selection processes in young cross-country skiers. Aim: (1) to analyze the effect of age on anthropometric and physiological parameters in medium-to-high level cross-country skiers during the late teenage period; (2) to describe parameters' trend in selected talents after the late teenage period; (3) to define which characteristics during the late teenage period could discriminate against further talent selection. Method: We found 14 male (M) and nine (F) athletes in our database, identified as talents by regional teams during the late teenage period, who performed the same diagonal-stride roller-skiing incremental test to exhaustion at 17 and 18 years old. Of these, four M and three F teenagers performed four further evaluations, and were selected by the national team. Age effect during the late teenage period was verified on anthropometric and physiological parameters measured at maximal intensity (MAX), first (VT1), and second (VT2) ventilatory thresholds, and 3° and 6° of treadmill incline. An observational analysis allowed to evaluate parameters' trend after the late teenage period in selected athletes, and to determine possible characteristics early discriminating further selection. Results: During the late teenage period, height, weight, and BMI was still raising in M as well as V'O 2 at VT2 and 6° of treadmill incline (all P > 0.05). In F, mass-scaled V'O 2 MAX increased while heart rate (HR) at MAX and VT2 decreased (all P > 0.05). Since the late teenage period, all selected males showed maximal ventilation volumes, absolute V'O 2 at MAX, VT1, and VT2 that were within or above the 75th percentile of their group; the same was found in selected females for mass-scaled V'O 2 MAX, VT1, and VT2 time. After the late teenage period, all selected athletes showed an increasing trend for VT2 time, while a decreasing trend for sub-maximal energetic cost, %V'O 2 and HR. Discussion: During the late teenage period, males are still completing their maturation process. Since the late teenage period, some physiological parameters seem good indicators to early discriminate for further talents. A progressive increase in skiing efficiency was demonstrated in developing talents of both sexes after the late teenage period., (Copyright © 2020 Zoppirolli, Modena, Fornasiero, Bortolan, Skafidas, Savoldelli, Schena and Pellegrini.)

Aims: This field experiment examined whether trained people with type 1 diabetes mellitus (T1D) have similar cardiovascular and baroreflex alterations after a 21-km running race when compared to healthy people., Methods: Nine T1D (39.0 ± 11.1 yr; 175.0 ± 10.2 cm; 70.8 ± 8.7 kg) were matched with 9 healthy participants (42.4 ± 5.8 yr; 175.7 ± 6.7 cm; 72.1 ± 8.5 kg) who ran an official half-marathon. Before and 1-hour after the race, cardiovascular variables, sympathetic activity (catecholamines), parasympathetic (heart rate variability analysis) modulation and cardiac baroreflex function (transfer function analysis) were assessed during supine rest and a squat stand test (forced blood pressure change)., Results: Performance time and weight loss [104.0 ± 13.2 and 111.0 ± 18.7 min; -2.57 ± 1.05 kg (-1.88 ± 0.88%) and -2.29 ± 1.15 kg (-1.59 ± 0.59%)] for healthy and T1D participants, respectively) were similar. Before running, no significant differences in any cardiovascular or autonomic variables were noted between the groups. After 1 h of recovery, both groups exhibited post-exercise hypotension, accompanied by increased sympathetic activity, decreased parasympathetic modulation, and reduced cardiac baroreflex sensitivity., Conclusions: Our results showed that the pattern of change in cardiovascular and autonomic nervous activity to strenuous exercise are well maintained in T1D participants with a training history of at least 5 years., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Exercise physiological responses can be markedly affected by acute hypoxia. We investigated cardiac autonomic and physiological responses to different hypoxic training protocols. Thirteen men performed three exercise sessions (5×5-min; 1-min passive recovery): normoxic exercise at 80% of the power output (PO) at the first ventilatory threshold (N), hypoxic exercise (FiO 2 =14.2%) with the same PO as N (HPO) and hypoxic exercise at the same heart rate (HR) as N (HHR). PO was lower in HHR (21.1±9.3%) compared to N and HPO. Mean HR was higher in HPO (154±11 bpm, p<0.01) than N and HHR (139±10 vs. 138±9 bpm; p=0.80). SpO 2 was reduced (p<0.01) to a similar extent (p>0.05) in HPO and HHR compared to N. HR recovery (HRR) and HR variability indices were similar in N and HHR (p>0.05) but reduced in HPO (p<0.05), mirroring a delayed parasympathetic reactivation. Blood lactate and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.001). During recovery oxygen consumption and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.01). Moderate HR-matched hypoxic exercise triggers similar cardiac autonomic and physiological responses to normoxic exercise with a reduced mechanical load. On the contrary, the same absolute intensity exercise in hypoxia is associated with increased exercise-induced metabolic stress and delayed cardiac autonomic recovery., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Mitochondrial encephalomyopathy, lactic acidosis, and recurrent stroke-like episodes syndrome (MELAS) is a rare degenerative disease. Recent studies have shown that resistant training (RT) can ameliorate muscular force in mitochondrial diseases. However, the effects of RT in MELAS are unknown. The aim of this case report was to investigate the effects of RT on skeletal muscle and mitochondrial function in a 21-years old patient with MELAS. RT included 12 weeks of RT at 85% of 1 repetition maximum. Body composition (DXA), in vivo mitochondrial respiration capacity (mVO 2 ) utilizing Near-infrared spectroscopy on the right plantar-flexor muscles, maximal voluntary torque (MVC), electrically evoked resting twitch (EET) and maximal voluntary activation (VMA) of the right leg extensors (LE) muscles were measured with the interpolated twitch technique. The participant with MELAS exhibited a marked increase in body mass (1.4 kg) and thigh muscle mass (0.3 kg). After the training period MVC (+5.5 Nm), EET (+2.1 N⋅m) and VMA (+13.1%) were ameliorated. Data of mVO 2 revealed negligible changes in the end-exercise mVO 2 (0.02 mM min -1 ), Δ mVO 2 (0.09 mM min -1 ), while there was a marked amelioration in the kinetics of mVO 2 ( τ mVO 2 ; Δ70.2 s). This is the first report of RT-induced ameliorations on skeletal muscle and mitochondrial function in MELAS. This case study suggests a preserved plasticity in the skeletal muscle of a patient with MELAS. RT appears to be an effective method to increase skeletal muscle function, and this effect is mediated by both neuromuscular and mitochondrial adaptations.

Objective: The aim of this study was to assess the short-term effectiveness of an intensive inpatient multidimensional rehabilitation program (MRP), including diet, exercise, and behavioral therapy, in elderly patients with severe obesity., Methods: Forty-four elderly patients (old; age 69.3 ± 3.5 years, BMI 41.9 ± 14.9) were analyzed against 215 younger patients (young; age 48.2 ± 18.5 years, BMI 43.9 ± 9.4), who were used as controls. All patients underwent MRP, based on group therapy guided by a multidisciplinary team (physicians, dietitians, exercise trainers, psychologists). We evaluated changes in anthropometry, cardiovascular risk factors, physical fitness, quality of life, and eating behavior., Results: After 3 weeks of MRP, we observed a reduction in body weight (old -3.8%, young -4.3%), BMI (old -3.9%, young -4.4%), waist circumference (old -3.4%, young -4.1%), total cholesterol (old -14.0%, young -15.0%), and fasting glucose (old -8.3%, young -8.1%), as well as improved performance in the Six-Minute-Walk Test (old +28.7%, young +15.3%), chair-stand test (old +24.8%, young +26.9%), and arm-curl test (old +15.2%, young +27.3%). Significant improvement was registered in all other analyzed domains., Conclusion: Our 3-week MRP provided significant clinical and functional improvement, which was similar between elderly and younger patients with severe obesity. In the long-term, this may be translated into better quality of life, through better management of obesity-associated morbidities and reduced frailty., (© 2019 The Author(s) Published by S. Karger AG, Basel.)

Purpose: This study investigated the effects of acute hypoxic exposure on post-exercise cardiac autonomic modulation following maximal cardiopulmonary exercise testing (CPET)., Methods: Thirteen healthy men performed CPET and recovery in normoxia (N) and normobaric hypoxia (H) (FiO 2  = 13.4%, ≈ 3500 m). Post-exercise cardiac autonomic modulation was assessed during recovery (300 s) through the analysis of fast-phase and slow-phase heart rate recovery (HRR) and heart rate variability (HRV) indices., Results: Both short-term, T30 (mean difference (MD) 60.0 s, 95% CI 18.2-101.8, p = 0.009, ES 1.01), and long-term, HRRt (MD 21.7 s, 95% CI 4.1-39.3, p = 0.020, ES 0.64), time constants of HRR were higher in H. Fast-phase (30 and 60 s) and slow-phase (300 s) HRR indices were reduced in H either when expressed in bpm or in percentage of HR peak (p < 0.05). Chronotropic reserve recovery was lower in H than in N at 30 s (MD - 3.77%, 95% CI - 7.06 to - 0.49, p = 0.028, ES - 0.80) and at 60 s (MD - 7.23%, 95% CI - 11.45 to - 3.01, p = 0.003, ES - 0.81), but not at 300 s (p = 0.436). Concurrently, Ln-RMSSD was reduced in H at 60 and 90 s (p < 0.01) but not at other time points during recovery (p > 0.05)., Conclusions: Affected fast-phase, slow-phase HRR and HRV indices suggested delayed parasympathetic reactivation and sympathetic withdrawal after maximal exercise in hypoxia. However, a similar cardiac autonomic recovery was re-established within 5 min after exercise cessation. These findings have several implications in cardiac autonomic recovery interpretation and in HR assessment in response to high-intensity hypoxic exercise.

Background: Despite being a recessive trait, the O blood group is the most frequent worldwide among the ABO blood types. Since running performance has been recognized as a major driver of evolutionary advantage in humans, we planned a study to investigate whether the ABO blood group may have an influence on endurance running performance in middle-aged recreational athletes., Methods: The study population consisted of 52 recreational, middle-aged, Caucasian athletes (mean age: 49±13 years, body mass index, 23.4±2.3 kg/m 2 ), regularly engaged in endurance activity. The athletes participated to a scientific event called "Run for Science" (R4S), entailing the completion of a 21.1 km (half-marathon) run under competing conditions. The ABO blood type status of the participants was provided by the local Service of Transfusion Medicine., Results: In univariate analysis, running performance was significantly associated with age and weekly training, but not with body mass index. In multiple linear regression analysis, age and weekly training remained significantly associated with running performance. The ABO blood group status was also found to be independently associated with running time, with O blood type athletes performing better than those with non-O blood groups. Overall, age, weekly training and O blood group type explained 62.2% of the total variance of running performance (age, 41.6%; training regimen, 10.5%; ABO blood group, 10.1%)., Conclusions: The results of our study show that recreational athletes with O blood group have better endurance performance compared to those with non-O blood group types. This finding may provide additional support to the putative evolutionary advantages of carrying the O blood group., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Purpose: To examine the effects of the world's most challenging mountain ultramarathon (MUM, 330 km, cumulative elevation gain of +24,000 m) on the energy cost and kinematics of different uphill gaits. Methods: Before (PRE) and immediately after (POST) the competition, 19 male athletes performed three submaximal 5-min treadmill exercise trials in a randomized order: walking at 5 km·h -1 , +20%; running at 6 km·h -1 , +15%; and running at 8 km·h -1 , +10%. During the three trials, energy cost was assessed using an indirect calorimetry system and spatiotemporal gait parameters were acquired with a floor-level high-density photoelectric cells system. Results: The average time of the study participants to complete the MUM was 129 h 43 min 48 s (range: 107 h 29 min 24 s to 144 h 21 min 0 s). Energy costs in walking (-11.5 ± 5.5%, P < 0.001), as well as in the first (-7.2 ± 3.1%, P = 0.01) and second (-7.0 ± 3.9%, P = 0.02) running condition decreased between PRE and POST, with a reduction both in the heart rate (-11.3, -10.0, and -9.3%, respectively) and oxygen uptake only for the walking condition (-6.5%). No consistent and significant changes in the kinematics variables were detected ( P -values from 0.10 to 0.96). Conclusion: Though fatigued after completing the MUM, the subjects were still able to maintain their uphill locomotion patterns noted at PRE. The decrease (improvement) in the energy costs was likely due to the prolonged and repetitive walking/running, reflecting a generic improvement in the mechanical efficiency of locomotion after ~130 h of uphill locomotion rather than constraints imposed by the activity on the musculoskeletal structure and function.

Point-of-care molecular diagnostic devices are a rapidly expanding market. A variety of technologies are being developed for DNA detection and amplification, mostly aiming to detect pathogens. Of the two devices for detection of human genetic variations, both focus on CYP2C19 and have obtained regulatory approval. Most other devices have not obtained US FDA approval and are still undergoing clinical trials. Most, if not all, devices in development require equipment to which disposable test cartridges are placed. Thus, they may not fulfill FDA's definition of being 'simple'. There is a clear need to develop completely disposable devices that do not require equipment maintenance, and to detect other genetic variants predictive of disease susceptibility and drug response.

This study aimed to determine whether the fatigue induced by a mountain ultramarathon (MUM) led to changes in energy cost and kinematic during level and graded running. Pre- and post-race, 14 ultratrail runners ran on a level, uphill (5%) and downhill (5%) treadmill at 10 km · h(-1). Kinematic data were acquired using a photocell system. Post-race, the downhill energy cost increased by 13.1% (P < 0.001). No change was noted in level and uphill running. Duty factor and stride frequency were increased, whereas swing time, cycle time and stride length were decreased in all conditions (P < 0.05). Contact time was increased and the rate of force generation was decreased only in the uphill and downhill conditions (P < 0.05). Positive correlations were observed between performance time and the pre- to post-changes in the energy cost of level (r = 0.52, P = 0.04) and uphill running (r = 0.50, P = 0.04). MUM-induced fatigue resulted in physiological and spatiotemporal changes, though the response to fatigue varied considerably between running conditions. These changes resulted in a significant increment only in the downhill energy cost. Incorporating downhill locomotion in the training programmes of ultratrailers may help to improve performance-related physiological and biomechanical parameters.

Background: Running economy and performance in middle distance running depend on several physiological factors, which include anthropometric variables, functional characteristics, training volume and intensity. Since little information is available about hematological predictors of middle distance running time, we investigated whether some hematological parameters may be associated with middle distance running performance in a large sample of recreational runners., Methods: The study population consisted in 43 amateur runners (15 females, 28 males; median age 47 years), who successfully concluded a 21.1 km half-marathon at 75-85% of their maximal aerobic power (VO2max). Whole blood was collected 10 min before the run started and immediately thereafter, and hematological testing was completed within 2 hours after sample collection., Results: The values of lymphocytes and eosinophils exhibited a significant decrease compared to pre-run values, whereas those of mean corpuscular volume (MCV), platelets, mean platelet volume (MPV), white blood cells (WBCs), neutrophils and monocytes were significantly increased after the run. In univariate analysis, significant associations with running time were found for pre-run values of hematocrit, hemoglobin, mean corpuscular hemoglobin (MCH), red blood cell distribution width (RDW), MPV, reticulocyte hemoglobin concentration (RetCHR), and post-run values of MCH, RDW, MPV, monocytes and RetCHR. In multivariate analysis, in which running time was entered as dependent variable whereas age, sex, blood lactate, body mass index, VO2max, mean training regimen and the hematological parameters significantly associated with running performance in univariate analysis were entered as independent variables, only MPV values before and after the trial remained significantly associated with running time. After adjustment for platelet count, the MPV value before the run (p = 0.042), but not thereafter (p = 0.247), remained significantly associated with running performance., Conclusion: The significant association between baseline MPV and running time suggest that hyperactive platelets may exert some pleiotropic effects on endurance performance.

Designing a wireless power transmission system(WPTS) using inductive coupling has been investigated extensively in the last decade. Depending on the different configurations of the coupling system, there have been various designing methods to optimise the power transmission efficiency based on the tuning circuitry, quality factor optimisation and geometrical configuration. Recently, a 3-coil WPTS was introduced in retinal prosthesis to overcome the low power transferring efficiency due to low coupling coefficient. Here we present a method to analyse this 3-coil WPTS using the S-parameters to directly obtain maximum achievable power transferring efficiency. Through electromagnetic simulation, we brought a question on the condition of improvement using 3-coil WPTS in powering retinal prosthesis.

In this paper, we present a precise charge balancing and compliance voltage monitoring stimulator front-end for 1024-electrode retinal prosthesis. Our stimulator is based on current mode stimulation. To generate a precisely matched biphasic current pulse, a dynamic current copying technique is applied at the stimulator front-end. A compliance voltage monitoring circuitry is included at the stimulator front-end to detect if a voltage across electrode-tissue interface goes beyond a predefined compliance voltage. Simulation results show the mismatch of a biphasic current pulse (at a maximum stimulation current of 476µA) is less than 0.1%. Also, the stimulator issues alarm signals, when a voltage compliance occurs during stimulation due to high tissue impedance. Our stimulator is implemented using a 65nm low voltage (LV) CMOS process, which helps reducing implementation area and power consumption.