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Background:Sarcopenia (SA) is a progressive skeletal muscle disorder, associated with increased risk of adverse outcomes, including falls, fractures, physical disability and mortality. Several risks factors may contribute to the development of SA in the elderly; among them, nutrition plays a key role in muscle health. The elderly are at risk of inadequate intake in terms of micronutrients affecting muscle homeostasis, such as B vitamins, related to homocysteine (Hcy) metabolism.Objectives and methods:This narrative review analysed the association between increased Hcy levels and SA, according to the criteria of the International Working Group on Sarcopenia, the European Working Group on Sarcopenia in Older People and the Asian Working Group for Sarcopenia. The authors focused not only on SA per se but also on exploring the association between increased Hcy levels and components of SA, including muscle mass, muscle strength and physical performance.Results:Results are inconsistent, except for muscle mass, showing no significant associations with Hcy levels.Conclusions:Few and conflicting data emerged in this review on the association between SA and increased Hcy levels due to numerous differences between studies that change the significance of the association of Hcy and SA, as well as the muscle strength, muscle mass and physical performance. Furthermore, because the ageing process is not uniform in the population owing to differences in genetics, lifestyle and general health, chronological age fails to address the observed heterogeneity among the ‘elderly’ of the studies reported in this revision. Therefore, further studies are still needed.

The purpose of the present study was to evaluate the Pearson correlations between hemodynamic parameters obtained with near infrared spectroscopy (NIRS), namely total hemoglobin (tHb) and tissue oxygen index (TOI %), as indicators of blood flow and oxygen extraction, and myoelectric parameters obtained with surface multichannel electromyography (sEMG), namely fractal dimension (FD) and conduction velocity (CV) slopes, as descriptors of central and peripheral fatigue, during sustained high level isometric contractions at 60% maximal voluntary contraction (MVC), in elderly subjects. Ten recreationally healthy elderly subjects (age 67.7 ± 4.6 years), 5 males and 5 females, performed one isometric contraction of the elbow flexors at 120° joint angle at 60% of MVC until exhaustion in two subsequent trials 1 week apart, one for the sEMG and the other one for NIRS recordings from the biceps brachii. A negative strong Pearson’s correlation between TOI % slope in the functional hyperemic phase (HP) of contraction and a positive correlation between the slope of TOI % recorded during the ischemic phase (IP) and the CV slope were found (r = − 0.76, P

A majority of patients with facioscapulohumeral muscular dystrophy (FSHD) report severe fatigue. The aim of this study was to explore whether fatigability during a performance task is related to the main clinical features of the disease in mildly affected patients. A total of 19 individuals with a molecular genetic-based diagnosis of FSHD (median D4Z4 deletion length of 27 kb) performed two isometric flexions of the dominant biceps brachii at 20% of their maximal voluntary contraction (MVC) for 2 min, and then at 60% MVC until exhaustion. Fatigability indices (average rectified value, mean frequency, conduction velocity, and fractal dimension) were extracted from the surface electromyogram (sEMG) signal, and their correlations with age, age at onset, disease duration, D4Z4 contraction length, perceived fatigability, and clinical disability score were analyzed. The conduction velocity during the low level contraction showed a significant negative correlation with the age at onset (p < 0.05). This finding suggest the assessment of conduction velocity at low isometric contraction intensities, as a potential useful tool to highlight differences in muscle involvement in FSHD patients.

Carnitine palmitoyltransferase II (CPTII) deficiency is the most frequent inherited disorder regarding muscle fatty acid metabolism, resulting in a reduced mitochondrial long-chain fatty acid oxidation during endurance exercise. This condition leads to a clinical syndrome characterized by muscle fatigue and/or muscle pain with a variable annual frequency of severe rhabdomyolytic episodes. While since the CPTII deficiency discovery remarkable scientific advancements have been reached in genetic analysis, pathophysiology and diagnoses, the same cannot be said for the methods of treatments. The current recommendations remain those of following a carbohydrates-rich diet with a limited fats intake and reducing, even excluding, physical activity, without, however, taking into account the long-term consequences of this approach. Suggestions to use carnitine and medium chain triglycerides remain controversial; conversely, other potential dietary supplements able to sustain muscle metabolism and recovery from exercise have never been taken into consideration. The aim of this review is to clarify biochemical mechanisms related to nutrition and physiological aspects of muscle metabolism related to exercise in order to propose new theoretical bases of treatment which, if properly tested and validated by future trials, could be applied to improve the quality of life of these patients.

In the mild subtype of inherited carnitine palmitoyltransferase II (CPTII) deficiency, muscular mitochondrial fatty acid β-oxidation is impaired. In this condition, interventions involve daily dietary restriction of fats and increase of carbohydrates, whereas physical exercise is commonly contraindicated due to the risk of muscle pain and rhabdomyolysis. We present the case of a 14-year-old female with CPTII deficiency who underwent a 1-h session of unsupervised exercise training for 6 months, 3 days per week, including interval and resistance exercises, after diet assessment and correction. Before and after intervention, the resting metabolic rate (RMR) and respiratory quotient (RQ) were measured by indirect calorimetry, and a cardiopulmonary exercise test (CPET, 10 W/30 s to exhaustion) was performed. Interval training consisted of a 1 min run and a 5 min walk (for 15 min progressively increased to 30 min). During these efforts, the heart rate was maintained over 70% HR max corresponding to respiratory exchange ratio (RER) of 0.98. Resistance training included upper/lower split workouts (3 sets of 8 repetitions each, with 2 min rest between sets). Blood CK was checked before and 36 h after two training sessions chosen randomly without significant difference. After training, RMR increased (+8.1%) and RQ lowered into the physiological range (from 1.0 to 0.85). CPET highlighted an increase of peak power output (+16.7%), aerobic performance (VO2 peak, 8.3%) and anaerobic threshold (+5.7%), oxygen pulse (+4.5%) and a much longer isocapnic buffering duration (+335%). No muscle pain or rhabdomyolysis was reported. Results from our study highlight that training based on short-duration high-intensity exercise improves overall metabolism and aerobic fitness, thus being feasible, at least in a case of CPTII deficiency.

Purpose In facioscapulohumeral muscular dystrophy (FSHD) fatigue is a major complaint. We aimed to investigate whether during isometric sustained elbow flexions, performance fatigability indexes differ in patients with FSHD with respect to healthy controls. Methods Seventeen patients with FSHD and seventeen healthy controls performed two isometric flexions of the dominant biceps brachii at 20% of their maximal voluntary contraction (MVC) for 2 min and then at 60% MVC until exhaustion. Muscle weakness was characterized as a percentage of predicted values. Maximal voluntary strength, endurance time and performance fatigability indices (mean frequency of the power spectrum (MNF), muscle fiber conduction velocity (CV) and fractal dimension (FD)), extracted from the surface electromyogram signal (sEMG) were compared between the two groups. Results In patients with FSHD, maximal voluntary strength was 68.7% of predicted value (p p r = 0.62) and lower levels of performance fatigability, characterized by reduced rate of changes in MNF (p r = 0.56), CV (p p r = 0.51) and increased endurance time (p r = 0.63), during the isometric contraction at 60% MVC. Conclusion A decreased reduction in the slopes of all the considered sEMG parameters during sustained isometric elbow flexions suggests that patients with FSHD experience lower levels of performance fatigability compared to healthy controls.

This study aimed to establish the Dual-Energy X-ray Absorptiometry (DXA)-derived Visceral adipose tissue (VAT) reference values for gender and assess the metabolic outcomes associated to the VAT in a cohort of elderly patients. The sample included 795 elderly patients (226/569: men/women) aged 65&ndash, 100 years (mean age 80.9 &plusmn, 7.5ys). Body composition measures and VAT were assessed by DXA and Core-Scan software. Biochemical analysis and a multidimensional comprehensive geriatric assessment were performed. VAT percentiles at the level of 5, 25, 50, 75, 95 were found in males at the following levels: 246, 832, 1251, 1769, 3048 cm3 and for females at 99, 476, 775, 1178, 2277 cm3. Moreover, this study showed that DXA-VAT was associated to a worsening of lipid, glycemic, hematocrit and kidney profile. Further studies will be needed in order to implement these findings in order to define the (DXA)-derived VAT levels associated to the frailty related risk factors in elderly.

Dates have a low glycemic index and are a source of antioxidants but, nevertheless, contain more than 70% sugar. This study aims to assess the effects of date consumption (three dates daily) on glycemic profile (HbA1c), body mass index (BMI), quality of life, and lipid profile, including total cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) in terms of safety for type 2 diabetic mellitus (T2DM) subjects. A randomized controlled trial was conducted with a sample of 100 T2DM subjects (39 male and 61 female) randomly assigned in two groups. The first group received three dates daily for 16 weeks, and the control group avoided date consumption. After a 16-week follow-up period, the study results showed an improvement of lipid profile with a statistically significant decrease in total cholesterol of ∆ = &minus, 0.209 mmol/L (confidence interval (CI) 95% &minus, 0.358, &minus, 0.059, p &lt, 0.05) and in LDL of ∆ = &minus, 0.171 mmol/L (CI 95% &minus, 0.358, 0.016) in the group receiving three dates daily. Intra-group mean differences of BMI were not statistically different in both groups after 16 weeks of date consumption. Even HbA1c did not change, both within and between groups after date consumption (∆ = 0.087%, CI 95% &minus, 0.086, 0.261). Between groups, mean difference changes (intervention minus control) showed a statistically significant improvement of quality of life index of ∆ = &plusmn, 30.66 points (CI 95% 12.45, 48.23) due to the consequent improvement in mental health. Although the definitive effect of dose/intake response of date consumption on Hb1Ac, lipid profile, and BMI in T2DM subjects is still to be established, the study suggests that dates could potentially have a beneficial effect on lipid profile, especially in reducing total cholesterol and elevating HDL, because of its high polyphenolic content. In addition, a low&ndash, moderate consumption of dates did not impact glucose levels because of dates&rsquo, low glycemic index.

The topic of creatine supplementation has received considerable attention for more than two decades, and it is likely to get even more attention, given that creatine plays such an essential role in skeletal muscle physiology. Creatine is an endogenous guanidine compound, which is synthesized starting from three amino acids ( methionine , glycine , and arginine ), able to influence muscle biochemical processes involved in energy production and recovery from exercise. In several experimental conditions the potential of creatine supplementation on anaerobic and aerobic performance has been extensively established. Other evidence suggests that creatine may exert beneficial effects to increase muscle hypertrophy and to reduce muscle damage by regulating various mechanisms, such as muscle fiber gene expression, inflammatory response, oxidative stress, calcium homeostasis, and satellite cell activity. The goal of this chapter is to examine the results of existing studies on creatine supplementation and its role on skeletal muscle physiology in healthy humans.

To counteract muscle mass, muscle strength and power loss during aging, and to study age-related change of neuromuscular manifestation of fatigue in relation to nutritional supplementation.randomized controlled double-blind study.Twice-daily consumption for 12 weeks of an Essential Amino Acids (EAA)-based multi-ingredient nutritional supplement containing EAA, creatine, vitamin D and Muscle Restore Complex®.38 healthy elderly subjects (8 male, 30 female; age: 68.91±4.60 years; body weight: 69.40±15.58 kg; height: 1.60±0.09 m) were randomized and allocated in supplement (SUPP) or placebo (PLA) group. Mean Measurements: Vitamin D blood level; Appendicular Lean Mass (ALM); Visceral Adipose Tissue (VAT); Maximal Voluntary Contraction (MVC) and Peak Power (PP); myoelectric descriptors of fatigue: Fractal Dimension and Conduction Velocity initial values (FD iv, CV iv), their rates of change (FD slopes, CV slopes) and the Time to perform the Task (TtT). Mean Results: Significant changes were found in SUPP compared to baseline: Vitamin D (+8.73 ng/ml; p0.001); ALM (+0.34 kg; p0.001); VAT (-76.25 g; p0.001); MVC (+0.52 kg; p0.001); PP (+4.82 W; p0.001). Between group analysis (SUPP Vs. PLA) showed improvements: vitamin D blood levels (+11,72 ng/ml; p0.001); Legs FFM (+443.7 g; p0.05); ALM (+0.53 kg; p0.05); MVC (+1.38 kg; p0.05); PP (+9.87 W; p0.05). No statistical changes were found for FD iv, CV iv, FD and CV slopes and TtT, either compared to baseline or between groups. Significant correlations between mean differences in SUPP group were also found.The study demonstrates that in healthy elderly subjects an EAA-based multi-ingredient nutritional supplementation of 12 weeks is not effective to change myoelectric manifestation of fatigue and TtT failure but can positively affect muscle mass, muscle strength, muscle power and VAT, counterbalancing more than one year of age-related loss of muscle mass and strength.

Musculoskeletal disorders in aging and pain are closely connected because of multiple mechanisms leading to loss of mobility and autonomy. Pain is predictive of diability and worsening frailty and the strength of this relationship increases with the severity of pain. This study presents a systematic review of randomized controlled trials, cross sectional studies, and observational studies based on treatment of pain in adults with musculoskeletal disorders using nutritional non-pharmacological (nutrients and antioxidants) interventions. The review found the efficiency of the following topics: (a) accession of the patient to a dietary counselling (e.g., daily recommended amount of protein—equivalent to at least of 1 g of protein per kilogram of body weight); (b) intake of glutamic acid-rich such as soy, egg, and cod and tryptophan-rich foods such as milk and peanuts—or taking quick-acting, free-form supplements; (c) supplementation of vitamin D and magnesium, if lacking; (d) weekly consumption of fish or supplements of omega-3 fatty acids; and (e) availability of botanicals, in particular curcumin and gingerol. These non-pharmacological interventions can help the pain therapist to create a personalized medicine (precision medicine), acting with the maximum efficacy and safety, and also reducing the dosage of analgesic drugs needed.

Modifiable risk factors for hamstring injury include lack of strength, fatigue and muscle strength asymmetry. Assessing lower body strength in the field is problematic as “gold standard assessment” are expensive, non-portable and assessment is time-consuming. Therefore, the objective of this study was to examine the validity and reliability of an adapted aneroid sphygmomanometer test of hamstring and quadricep strength. In 14 active males (age 23.1 ± 2.5 years; height 180.9 ± 8.2 cm; weight 88.4 ± 8.5 kg). concurrent validity was assessed by comparing the adapted sphygmomanometer assessment at 30 and 90° of knee flexion to isokinetic dynamometry using Pearson product-moment correlation. The reliability of the adapted sphygmomanometer was assessed in 10 professional rugby players (age 21.5 ± 2.6 years; height 177.2 ± 5.8 cm; weight 92.7 ± 5.8 kg ) across two visits. Sphygmomanometer strength assessments of hamstring and quadriceps were associated with isokinetic measures (Quadricep: right, r = 0.386, 95% CI = 0.136–0.866, p < 0.05; left, r = 0.431, 95% CI = 0.193–0.880, p < 0.05), hamstring strength at 90° of knee flexion (Hamstring: right, r = 0.545, 95% CI = 0.342–0.912, p < 0.01; left, r = 0.643, 95% CI = 0.473–0.935, p < 0.001) and hamstring strength at 30° of knee flexion (right, r = 0.329, 95% CI = 0.062–0.846, p < 0.05; left, r = 0.387, 95% CI = 0.138–0.867, p < 0.05). However, the adapted test was not able to identify bilateral or hamstring to quadricep asymmetry. Test–retest reliability was high for most assessments (ICC range: 0.64–0.92), and SEM measures ranged between 5 and 12%, with the smallest change representing a change in strength ranging between 3 and 4%. In conclusion, an adapted sphygmomanometer test for hamstring and quadricep strength assessment was valid and reliable in assessing hamstring and quadricep strength but not bilateral or hamstring and quadricep asymmetry.

Background: The purpose of this study was to investigate the acute effects of a single oral administration of an essential amino acids enriched mixture (EAA) on myoelectric descriptors of fatigue and maximal force production after a resistance exercise protocol (REP).Methods: Twenty adult males (age: 27 ± 6 years; body mass: 72.7 ± 7.50 kg; height: 1.76 ± 0.06 m) were enrolled in a double-blind crossover placebo-controlled study. Subjects were randomized to receive EAA mix (0.15 g/kg BM) or a placebo (PLA) in two successive trials 7 days apart. In both trials subjects completed a REP 2 h after the ingestion of the EAA mix or PLA. Before ingestion and after REP subjects performed isometric contractions of the dominant upper limb with the elbow joint at 120 degrees: (1) two maximal voluntary contractions (MVCs) for 2–3 s; (2) at 20% MVC for 90 s; (3) at 60% MVC until exhaustion. Mean values of MVC, conduction velocity initial values (CV), fractal dimension initial values (FD), their rates of change (CV slopes, FD slopes) and the Time to perform the Task (TtT) were obtained from a multichannel surface electromyography (sEMG) recording technique. Basal blood lactate (BL) and BL after REP were measured.Results: Following REP a significant decrease of MVC was observed in PLA (P < 0.05), while no statistical differences were found in EAA between pre-REP and post-REP. After REP, although a significant increase in BL was found in both groups (P < 0.0001) a higher BL Δ% was observed in PLA compared to EAA (P < 0.05). After REP, at 60% MVC a significant increase of CV rate of change (P < 0.05) was observed in PLA but not in EAA. At the same force level TtT was longer in EAA compared to PLA, with a significant TtT Δ% between groups (P < 0.001).Conclusion: Acute EAA enriched mix administration may prevent the loss of force-generating capacity during MVC following a REP. During isometric contraction at 60% MVC after REP the EAA mix may maintain CV rate of change values with a delay in the TtT failure.

Background : Fish protein hydrolysates (FPHs) have been reported as a suitable source of proteins for human nutrition because of their balanced amino acid composition and positive effect on gastrointestinal absorption. Objective : Here, we investigated the effect of a FPH, Slimpro ® , obtained from blue whiting ( Micromesistius poutassou ) muscle by enzymatic hydrolysis, on body composition and on stimulating cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1) secretion. Design : A randomized clinical study was carried out on 120, slightly overweight (25 kg/m 2 ≤ BMI

In this paper, dimensional analysis is adopted to study fluid flow distribution and temperature distribution in disc-type ON (oil natural) cooled transformer windings. Theoretical analysis on the thermal driving force and the pressure drop in the liquid circulation loop is also performed to determine the total liquid flow rate in the transformer. The thermal performance of three different liquids, a hydrocarbon mineral oil, a hydrocarbon gas-to-liquid (GTL) oil and a synthetic ester are investigated using computational fluid dynamics (CFD) simulations, based on the understanding from dimensional analysis and the flow rates determined from the theoretical analysis. It is found in the investigated conditions that the hydrocarbon mineral and GTL oil share similar thermal performance; the synthetic ester has a lower total flow rate due to its higher viscosity and therefore requires additional effort to improve the thermal performance.

This systematic review aimed to investigate the association of fish and sea fish dietary patterns (FishDiet) and meat or processed meat dietary patterns (MeatDiet) with bone mineral density (BMD) and/or risk of fractures (RF). This review includes 37 studies with a total of 432,924 subjects. The results suggest that MeatDiet and FishDiet did not affect BMD or RF in 48.2% of the subjects with MeatDiet and in 86.5% of the subjects with FishDiet. Positive effects on bone were found in 3% of subjects with MeatDiet and in 12% with FishDiet. Negative effects on bone were observed in 2.7% of FishDiet and in 47.9% of MeatDiet. Major negative effects of MeatDiet were found in subjects located in the Netherlands, Greece, Germany, Italy, Norway, UK and Spain who do not sustain a Mediterranean diet (92.7%); in Korea (27.1%); in Brazil and Mexico (96.4%); and in Australia (62.5%). This study suggests that protein intake from fish or meat is not harmful to bone. Negative effects on bone linked to FishDiet are almost null. Negative effects on bone were associated to MeatDiet in the setting of a Western Diet but not in Mediterranean or Asian Diets.

Despite the numerous positive effects of physical exercise, some negative physiological changes occur in long-lasting heavy training with transient dysfunction of the immune system, increased inflammation, and oxidative stress. This is the case of elite athletes, who train intensively to compete at the highest levels. However, these athletes can counteract the negative effects of heavy training, reducing acute and chronic inflammations and supporting the immune system, with nutritional and supplementation countermeasures. For this purpose, macronutrient manipulation with an appropriate use of certain supplements can be considered as an intervention to reduce exercise-induced immune changes and inflammatory risk. For example, branched-chain amino acid (BCAA) supplementation may promote such immune responses in skeletal muscle. Furthermore, micronutrients play an important role in immune function; in particular, the antioxidant capacity of several dietary micronutrients (e.g., tocopherols, docosahexaenoate, and flavonoids) is very interesting to support the endogenous antioxidant defense systems of the athletes, counterbalancing the negative effects of oxidative damage due to free radicals. Some of these nutrients have potential anti-inflammatory properties as assessed by the attenuated levels of interleukin-6 (IL-6) and C-reactive protein (CRP). Key Teaching Points: Long-lasting heavy training plan and competition can lead to chronic immune suppression in athletes, increasing infection risk. Chronic exercise increases mobilization of neutrophils, decreases mobilization of lymphocytes, and decreases the absolute and relative numbers of neutrophils at rest. Nutritional deficiencies alter the immuno-system and increase infection risk. Nutrition can influence exercise-induced immune suppression. Elite athletes competing at the highest levels can benefit from nutritional and supplementation support to improve immunity and reduce acute and chronic inflammations.

Aging is an inevitable biological process, characterized by a general decline in physiological and biochemical functions of major body systems. In the case of the neuromuscular system, reductions in strength and mobility cause a deterioration in motor performance, impaired mobility, and disability. At the cellular level, aging is caused by a progressive decline in mitochondrial function that results in accumulation of reactive oxygen species (ROS). As the level of oxidative stress in skeletal muscle increases with age, advancing age is characterized by an

As we age, the aerobic and functional capacities of our major physiological systems progressively decline. In the case of the neuromuscular system, reductions in strength and mobility cause a deterioration in motor performance and in turn a greater tendency to fall (with increased risk of fractures), impaired mobility, disability and loss of independence in the elderly. Given the increase in our life expectancy and the consequent growth in the elderly population, these conditions will have an increasing impact on modern healthcare systems, and their prevention and attenuation needs to be addressed. Several intervention strategies have been used to improve motor performance among the aging. At the cellular level, aging is caused by a progressive decline in mitochondrial function that results in the accumulation of reactive oxygen species (ROS) generated by the addition of a single electron to the oxygen molecule As the level of oxidative stress in skeletal muscle increases with age, the production of some antioxidant enzymes increases adaptively to compensate in part. The aging process is characterized by an imbalance between an increase in the production of reactive oxygen species in the organism and the antioxidant defences as a whole. The goal of this review is to examine the results of existing studies on oxidative stress in aging human skeletal muscles, taking into account different physiological factors (sex, fiber composition, muscle type and function).