Muscle Oxygen Delivery in the Forearm and in the Vastus Lateralis Muscles in Response to Resistance Exercise: A Comparison Between Nepalese Porters and Italian Trekkers

Altitude ascending represents an intriguing experimental model reproducing physiological and pathophysiological conditions sharing hypoxemia as the denominator. The aim of the present study was to investigate fractional oxygen extraction and blood dynamics in response to hypobaric hypoxia and to acute resistance exercises, taking into account several factors including different ethnic origin and muscle groups. As part of the “Kanchenjunga Exploration & Physiology” project, six Italian trekkers and six Nepalese porters took part in a high altitude trek in the Himalayas. The measurements were carried out at low (1,450 m) and high altitude (HA; 4,780 m). Near-infrared spectroscopy (NIRS)-derived parameters, i.e., Tot-Hb and tissue saturation index (TSI), were gathered at rest and after bouts of 3-min resistive exercise, both in the quadriceps and in the forearm muscles. TSI decreased with altitude, particularly in forearm muscles (from 66.9 to 57.3%), whereas the decrement was less in the quadriceps (from 62.5 to 57.2%); Nepalese porters were characterized by greater values in thigh TSI than Italian trekkers. Tot-Hb was increased after exercise. At altitude, such increase appeared to be higher in the quadriceps. This effect might be a consequence of the long-term adaptive memory due to the frequent exposures to altitude. Although speculative, we suggest a long-term adaptation of the Nepalese porters due to improved oxygenation of muscles frequently undergoing hypoxic exercise. Muscle structure, individual factors, and altitude exposure time should be taken into account to move on the knowledge of oxygen delivery and utilization at altitude

Effects of endurance, resistance and neuro-muscular electrical stimulation trainings to the anthropometric and functional mobility domains in elderly

Background and aims There\u2019s the need to increase physical activity engagement to promote healthy ageing. Different training protocols elicit different morpho-functional effects: the comprehension of the related assessment tests is a key to improve the specific proposals and to monitor adequately the adaptations. We aimed to identify the functional adaptation processes basing on different training protocols. Methods 40 healthy elderly (28 males and 12 females, 70.7 \ub1 4.39 y) were randomly divided into 4 groups: endurance, resistance, Neuro-Muscular Electrical Stimulation and control, trained for 12 weeks andex-post evaluated on anthropometric and functional domains. Results We found: significant effect for gender, time and time 7 protocols for Five Times Sit-to-Stand Test and Timed Up-and-Go test. Post-hoc analyses revealed effect for resistance and Neuro-Muscular Electrical Stimulation on Five Times Sit-to-Stand Test, and for endurance and Neuro-Muscular Electrical Stimulation on Timed Up-and-Go test. Correlations and factorial analysis linked Five Times Sit-to-Stand Test and Timed Up-and-Go test on the functional domain. Conclusions Medium-term physical interventions significantly modified functional characteristics of elderly. We found no ex-post effect on anthropometric parameters. The two functional tests are based on different underlying domains, our data therefore suggest to use both of them to specifically evaluate the training-induced functional adaptations in elderly. Our results promote the usefulness of evidence-based trainin

Effects of a vibrational proprioceptive stimulation on recovery phase after maximal incremental cycle test

Global Proprioceptive Resonance (GPR) is a recently developed approach conceived to solicit the various cutaneous mechanoreceptors, through application of mechanical multifocal vibration at low amplitude and at definite body sites, limiting the stimulation of the profound structures. This interventional study evaluated the effects of GPR on cardiorespiratory function during the post-exertional recovery period. A group of volunteers involved in Triathlon (a multisport discipline consisting of sequential swim, cycle, and run disciplines higly demanding in terms of metabolic engagment), underwent two maximal incremental exercise tests until exhaustion followed alternatively to (a) a 13 minutes section of GPR or (b) a standard low intensity exercise acute trend of the same duration. These effects of these two approaches were compared in terms of recovery of: heart rate (HR), respiratory rate (RR), peripheral oxygen saturation (SpO2) and venous lactate concentration (Lac). The physiological parameters (HR, RR, SpO2 and Lac) recorded in the pre-exertion session showed similar values between the 40 volunteers while several differences were recorded in the post-exertion phase. After 6 min of GPR recovery it was recorded a drop in RR below baseline (19.4±4.15 min-1 vs. 12.2± 0.4 min-1; p<0.001) coupled with an increase in peripheral oxygen saturation above the baseline (GPR: 99.0%±0.16% vs. 96.6%±0.77%, p<0.001). Moreover, the most striking result was the drop in lactate concentration measured after 13 min of GPR recovery: 84.5±3.5% in GPR vs 2.9±7.6% reduction in standard recovery (p<0.001). Notably no differences were recorded recovery of heart rate. GPR has promising effects on post-exercise recovery on RR, SpO2 and lactate level on young athletes. © 2020 PAGEPress Publications. All rights reserved

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

Uroflowmetry and Altitude Hypoxia: A Report from Healthy Italian Trekkers and Nepali Porters During Himalayan Expedition

: Hypoxia alters micturition, which influences bladder function by involving different neurological and humoral systems. In this study we assessed the mid-term effects of altitude hypoxia on uroflowmetry in healthy male lowlander native Nepali porters and Italian trekkers, four each, who coattended a Himalayan expedition. All the participants completed a 19-day trek along a demanding route with ascent and descent at the Kanchenjunga Mountain. They underwent micturition and urodynamic analysis twice, at low altitude of 665&nbsp;m&nbsp;a.s.l. and high altitude of 4,750&nbsp;m&nbsp;a.s.l. Statistical comparisons considered the altitude effects (low vs. high) and ethnicity (Italian vs. Nepali). Food consumption was recorded, and water and energy intake were calculated. We found trends of borderline significance in the mean urinary flow rate (Qmean) (p&nbsp;=&nbsp;0.058; effect size η2 p&nbsp;=&nbsp;0.478) and in Qmax to the advantage of the Nepali. There was no evidence of differences when comparing time to Qmax and urine volume at Qmax and Qmean for altitude or altitude × ethnicity. In addition, there was a lonely female participant, who, analyzed as a case report, showed increased Qmean at high altitude. Older age mitigated while energy intake potentiated the ethnic differences noted in uroflowmetry. We conclude that altitude hypoxia rather inappreciably affects micturition in healthy men. However, a trend for possible ethnic differences raises worthy of note perspectives on adaptive ability of micturition. Also, dietary intake and age should be considered as confounding elements when evaluating micturition

Effects of auto-selected intensity in neuromuscular electrical stimulation and resistance training on muscle responses and functional capacity of elderly people

Aim: Resistance training (RT) and neuromuscular electrical stimulation (NMES) are often used to combat sarcopenia and functional decline in elderly people. However, intensity is a barrier to adherence and regularity in training programs for this population. This study aimed to evaluate and compare the effects of RT and NMES, performed at autoselected intensity, on adaptive responses of the neuromuscular system and functional capacity in healthy elderly people. Methods: After health screening, the total sample (n = 18) was randomized into three groups: control group CO (age = 71.7 (1.9) yrs.; n = 6), NMES group (age = 68.8 (5.3) yrs.; n = 6) or RT group (age = 72.3 (6.1) yrs.; n = 6).The training groups performed a tenweek training period, while the CO group were advised to maintain their habitual lifestyle. Auto-selected load was determined as training intensity: The RT group used the maximal load to perform a range of 8\u201312 repetitions; the NMSE group trained at the pain threshold. Biopsies in the quadriceps muscles, strength and functional capacity were performed at the pre and post-training moments. Dependent variables included: (MVIC), predicted (1-RM), concentric isokinetic peak power and concentric power resistance of the quadriceps muscles and handgrip test to evaluate strength responses; the Five Times Sit-to-Stand test and the Timed Up and Go test performances, to evaluate the functional capacity; single fibre characteristics and satellite cell responses were used to evaluate muscle fibre responses. Results:RT positively affected 1-RM and MVIC performances. Both training protocols positively affected handgrip and functional capacity test performances. The CO group did not demonstrate improvements in strength performance, but did demonstrate decrements in functional capacity tests. Molecular and cellular responses did not present alterations after the training period. Conclusions: This study revealed that both RT and NMES protocols, using auto-selected loads, are valid strategies for promoting significant improvements in functional capacity in elderly people, even with modest improvements in strength capacity and an absence of alterations in myofibre responses

GOKIO KUMBU/AMADABLAM TREK 2012 : stabilometric adaptation in women to exercise training at low and high altitude

Purpose: Balance is the essential ability to maintain posture during physical activity and daily life. Exercise can have acute and chronic effects on postural stability. Individual exercise sessions can decrease postural stability, while long-term training improves balance and postural sway. Consequently, athletes and people undergoing training have better postural sway than more sedentary subjects. Hypobaric hypoxia has also been suggested to cause stress and adaptation of balance abilities. Thus, the aim of this study was to determine the effects of exercise training under normoxia and hypobaric hypoxia on postural sway. Methods: Seven adult females participated in this study. They underwent assessments of posture before and after 12&nbsp;days of low-to-moderate exercise training at low altitude, and the same 4&nbsp;months later, after 12&nbsp;days of exercise training at high altitude. The data collected included: centre of pressure, average speed oscillation, and Romberg Quotient. This generated a total of 56 posture tests for these seven subjects. Results and conclusions: The results of this research suggest that comparing the each period of activity (pre-exercise) and after the end of each period (post-exercise), both at low and at high altitudes, did not influence the postural stability

High altitude exercise: correlation between serum antioxidant defense system and anthropometrics profile

Generation of reactive oxygen species (ROS) increase during altitude exercise. ROS are neutralized by antioxidant defense systems consisting of several enzymes and non-enzymatic compounds among which, alpha-tocopherol, vitamins A, beta-carotene and lycopene play important roles. An imbalance between the oxidants and anti-oxidants can cause oxidative damages to cells and tissues. Several biomarkers are available to quantify the oxidatively-modified macromolecules. The assessment of malondialdehyde (MDA) and protein carbonyl content (PCC) are widely employed assays used to determine lipid peroxidation and oxidative damage to proteins, respectively. Since the ROS removal rate is mostly controlled by low molecular weight antioxidants, interest is growing in determining the total antioxidant status (TAS). We investigated the effect of a 43-days expedition ranging from 0 to 5900m on serum antioxidant defense system in 7 climbers (MANASLU 2008). TAS, PCC, MDA, lycopene and antioxidant vitamins concentrations were measured in serum before and immediately after expedition. No significant effects were observed in any parameters. Pre-expedition BMI and TAS were inversely correlated and the same correlation was demonstrated between TAS and fat mass. These correlations were lost in post-expedition subjects. Vit A and E expedition-induced variations were also positively associated. A progressively adaptive physical exercise in high altitude environment seem not to show a severe impact on the antioxidant-related biochemical human profile. Our results seem to indicate body mass and, in particular, fat mass percentage as possible factors involved in the antioxidant defense performance

Bisphosphonates Treatment in Metastatic Prostate Cancer

The skeleton is the third most common site for cancer to spread after the liver and lungs. Malignancies that can cause destruction of skeletal bones include multiple myeloma and metastatic diseases of the lung, prostate and other solid cancers. The clinical complications include pain, fractures, compression of the spinal cord and hypercalcemia of malignancy. Bisphosphonates are bone-seeking agents originally designed to treat loss of bone density. Accumulating data show that they are effective in diseases in which there is upregulation of osteoclastic or osteolytic activity. Bisphosphonates can reduce skeletal-related events and bone pain, as well as reduce the adverse effects of androgen deprivation therapy on skeletal integrity. However, it is clear that bisphosphonates do not represent a decisive treatment in the care of metastases but a therapeutic choice in synergy with regular anti-tumor drugs. The preclinical and clinical data to support this are reviewed here