Intensity of resistance exercise determines adipokine and resting energy expenditure responses in overweight elderly individuals

A single session of strength training changed plasma levels of resistin, but not leptin in overweight and obese men

Obesity has a complex multifactorial etiology and is characterized by excessive accumulation of adipose tissue. Visceral adipose tissue has deleterious effects on health because it secretes large amounts of inflammatory cytokines. Nutritional calorie restriction associated with strength training may be useful in managing chronic systemic inflammation. This study aimed to evaluate the acute effect of a single strength-training session on plasma adipokine levels in sedentary, overweight, and obese young men. This study included twelve men (Age: [34.95 ​± ​9.77] years; Height: [174.16 ​± ​3.66] centimeter [cm]; Weight: [97.83 ​± ​12.87] kilogram (kg); body mass index [BMI]: [32.30 ​± ​4.51] kg/m2), who performed a single strength training session. The strength training protocol consisted of 4 sets of 12 repetitions in the following six exercises, 45° leg press, bench press, leg extension, machine row, leg curl, and shoulder press. Blood samples were collected before, immediately after, and 1-h subsequent after strength training. The plasma levels of resistin and leptin were measured. A significant decrease in resistin levels were found 1 ​h after the strength training session if compared to levels before the training session (pre-[before] [2 390 ​± ​1 199] picograms per milliliter [pg/mL] vs post-1 h [1-h subsequent] [1 523 ​± ​798],6 ​pg/mL, p ​= ​0.002 8). The plasma leptin levels did not differ at any time point. In conclusion, a very well controlled single session of strength training significantly decreased the plasma levels of resistin without altering the concentration of leptin in overweight and obese individuals. This effect, at least in part, supports the benefits of exercise by reducing the low grade inflammation and insulin resistance in obesity.

Concentrations of Selected Adipocytokines in the Blood Plasma in Proximal Suspensory Desmopathy of Horses, with a Focus on Their Physical Activity-A Pilot Study

Chronic tendon and ligament diseases are commonly encountered in both athletic humans and animals, especially horses. Distal limb diseases, including suspensory ligament (SL) pathology due to anatomical, histological, and biomechanical properties, can be considered a model for tendon and ligament pathologies in humans. The appropriate selection of therapy is often crucial in optimising the healing process. One decisive factor influencing the possibility of returning to pre-disease training levels appears to be the utilisation of physical activity, including controlled movement, during the rehabilitation process. In the pathogenesis of musculoskeletal diseases and rehabilitation, adipocytokines play diverse roles. However, it is unclear what significance they hold in horses and in specific disease entities as well as the consequences of their mutual interactions. Recent studies indicate that in the pathogenesis of diseases with varied aetiologies in humans, their value varies at different stages, resulting in a diverse response to treatment. The results of this study demonstrate lower resistin concentrations in the venous blood plasma of horses with proximal suspensory desmopathy (PSD), while higher levels were observed in regularly trained and paddocked animals. The horses investigated in this study showed higher concentrations of resistin and IL-8, particularly in paddocked horses as well as in the working group of horses. The results suggest that these concentrations, including resistin in blood plasma, may be clinically significant. This attempt to explore the aetiopathogenesis of the processes occurring in the area of the proximal attachment of the suspensory ligament may optimise the procedures for the treatment and rehabilitation of horses.

Acute and Chronic Effects of Strength Training on Plasma Levels of Adipokines in Man

Adipose tissue is specialized cells that produce and release adipokines. Exercise may modulate adipokine production in adipocytes. The aim of this longitudinal study was to evaluate the acute and chronic effects of strength training (ST) on plasma levels of adiponectin, leptin, and resistin. Twelve untrained young male participants (23.42±2.67 years) were selected. The training protocol consisted of 3 exercises, with 3 sets of 65% of 1RM (one-repetition maximum) with pause of 90 s between sets with duration of 5 s/repetition (2 s conc/3 s ecc), 3 times a week for 10 weeks. Blood was collected at four time points: before and after the first ST session and before and after the last ST session. The comparisons between adipokine levels before and after the same training session showed acute changes, while the comparisons between levels before or after the first session versus before or after the last session revealed chronic alterations. ST increased adiponectin levels after the first exercise session in comparison to levels before this session [50 952 (46 568-51 894) pg/mL vs. 52 981 (49 901-54 467) pg/mL, p=0.019]. Similar differences were observed for resistin levels, which were higher after the last session compared to before [4 214.4 (±829) pg/mL vs. pre-S30 2 251.3 (±462.2) pg/mL, p=0.0008] and in the comparison between after the last and after the first ST sessions [4 214.4 (±829.0) pg/mL vs. 1 563.7 (±284.8) pg/mL, p=0.004]. Leptin levels acutely changed in the last training session. ST produced acute and chronic changes in plasma adipokines.

Long-term exercise training and inflammatory biomarkers in healthy subjects: a meta-analysis of randomized controlled trials

Objective

This meta-analysis investigated the effect of long-term exercise training (ET) including aerobic, resistance, and multicomponent ET on the levels of inflammatory biomarkers in randomized controlled trials (RCTs) involving healthy subjects.

Methods

We searched seven databases for articles until May 1st, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 16.0.

Result

Thirty-eight studies were included in the meta-analysis, involving 2,557 healthy subjects (mean age varies from 21 to 86 years). Long-term ET induced significantly decreased in the levels of interleukin-6 (IL-6) (SMD -0.16, 95% CI -0.30 to -0.03, p = 0.017), C-reactive protein (CRP) (SMD -0.18, 95% CI -0.31 to -0.06, p = 0.005), as well as tumor necrosis factor alpha (TNFα) (SMD -0.43, 95% CI -0.62 to -0.24, p < 0.001). Subgroup analysis revealed that Long-term ET conducted for more than 12 weeks and exercise of moderate intensity had greater anti-inflammatory effects. Meta-regression analysis showed that the reduction in CRP level induced by long-term ET was weakened by increasing exercise intensity.

Conclusion

Long-term ET induced significant anti-inflammatory effects in healthy subjects. Long-term ET-induced anti-inflammatory effects were associated with exercise of moderate intensity and training conducted for more than 12 weeks.Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/# myprospero, PROSPERO, identifier CRD42022346693.

Factors related to hypermetabolism in individuals with type 2 diabetes mellitus and non-alcoholic fatty liver disease

Considering the progressive prevalence and co-occurrence of type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD), as well as the current evidence suggesting the elevated levels of basal metabolic rate (BMR) among these individuals, the present study aimed to identify factors determining hypermetabolism in such subjects. This cross sectional study was conducted in 30 to 53-year-old individuals with concurrent T2DM and NAFLD (controlled attenuation parameter score ≥ 260 dB/m). Resting energy expenditure (REE) was determined by an indirect calorimetry device. Hypermetabolism was defined as an elevated measured REE > 110% of the predicted REE. The multivariate logistic regression test was used for detecting factors associated with hypermetabolism. Between September, 2017, and March, 2018, a total of 95 eligible participants (64.40% male) with both T2DM and NAFLD were included, while 32.63% of them were classified as hypermetabolic. Overall, the mean recruitment age ± standard deviation and median (interquartile range) body mass index were 44.69 ± 5.47 years and 30.20 (27.80-33.30) kg/m², respectively. Demographic, anthropometric and biochemical variables did not vary significantly across two groups except for total body water, low-density lipoprotein cholesterol and dipeptidyl peptidase 4 (DPP-4) inhibitors (p < 0.05). According to the results of multivariable logistic regression analyses, hypermetabolism had a positive association with adiponectin (odds ratio [OR] 1.167, 95% confidence interval [CI] 1.015-1.342, p = 0.030), physical activity (OR 1.134, 95% CI 1.002-1.284, p = 0.046), alanine transaminase (OR 1.062, 95% CI 1.006-1.122, p = 0.031) and diastolic blood pressure (OR 1.067, 95% CI 1.010-1.127, p = 0.021). However, fat free mass was inversely related to hypermetabolism (OR 0.935, 95% CI 0.883-0.991, p = 0.023). Adiponectin, alanine transaminase, physical activity, diastolic blood pressure and fat free mass were independently associated with hypermetabolism in subjects with NAFLD and T2DM.

Recent advances in cell-based and cell-free therapeutic approaches for sarcopenia

Sarcopenia is a progressive loss of muscle mass and function that is connected with increased hospital expenditures, falls, fractures, and mortality. Although muscle loss has been related to aging, injury, hormonal imbalances, and diseases such as malignancies, chronic obstructive pulmonary disease, heart failure, and kidney failure, the underlying pathogenic mechanisms of sarcopenia are unclear. Exercise-based interventions and multimodal strategies are currently being considered as potential therapeutic approaches to prevent or treat these diseases. Although drug therapy research is ongoing, no drug has yet been proven to have a substantial safety and clinical value to be the first drug therapy to be licensed for sarcopenia. To better understand the molecular alterations underlying sarcopenia and effective treatments, we review leading research and available findings from the systemic change to the muscle-specific microenvironment. Furthermore, we explore possible mechanisms of sarcopenia and provide new knowledge for the development of novel cell-free and cell-based therapeutics. This review will assist researchers in developing better therapies to improve muscle health in the elderly.

The Combinatory Effect of Spirulina Supplementation and Resistance Exercise on Plasma Contents of Adipolin, Apelin, Ghrelin, and Glucose in Overweight and Obese Men

Methods

The current investigation was conducted in a single-blind and quasiexperimental fashion. Sixty overweight and obese men (BMI > 25) ranging in age from 30 to 55 years were purposefully selected and randomly assigned to one of four groups: training plus spirulina (T+S), training plus placebo (T+P), spirulina (S), or placebo (P). For eight weeks, the (S) and (P) groups consumed two 500 mg spirulina and placebo capsules daily, respectively. Resistance training was performed three sessions a week over eight weeks, consisting of 12 movements with 1-, 2-, 3-, and 4-minute rest intervals and 40-90 percent maximal repetition. Adipolin, apelin, and ghrelin indices were measured before and after exercise using special kits.

Results

All variables changed significantly between groups except for apelin. Within-group comparisons revealed a substantial increase in adipolin levels in the (T+S) and (T+P) groups (P < 0.05). Apelin levels were decreased in the (T+S) and (T+P) groups. Additionally, FBS levels reduced significantly in (T+S) (P = 0.01).

Conclusion

It seems that eight weeks of circuit resistance training and spirulina supplementation can lead to reduced weight and apelin and FBS levels as well as increased concentrations of adipolin and ghrelin contents in overweight and obese men.

The Effects of Exercise on Appetite in Older Adults: A Systematic Review and Meta-Analysis

Background: The effect of physical activity and exercise on hunger and satiety has been well-studied in younger adults, but the influence of aging is less understood. While some evidence suggests that acute bouts of exercise induce a compensatory eating drive, long-term activity may improve satiety sensitivity. The objective of this study was to investigate the effects of exercise on appetite in older adults.

Methods: We systematically reviewed available literature investigating the effect of exercise on appetite in older adults adults (CRD42020208953). PubMed, PsycINFO, Academic Search Complete, the Sports Medicine & Education Index, and Web of Science, were searched for peer-reviewed articles published in English with no date restriction. Included studies implemented a primary exercise or physical activity intervention with a control group, on a generally healthy population ≥60 years of age. Selected studies included at least one appetite outcome. Risk of bias was assessed using the 11-point Physiotherapy Evidence Database (PEDro) tool. Standardized mean difference summary statistics (Hedge's g effect sizes) and 95% confidence intervals were reported.

Results: We identified 15 reports (13 studies) which met all inclusion criteria (5 resistance training, 3 aerobic, 6 mixed modalities). Studies included 443 participants (Age = 68.9 ± 5.2, 82.3% female) and had generally “good” bias scores (PEDro = 6.4 ± 0.88). Random effects meta-analyses revealed that the exercising group showed statistically significant reductions in glucose [SMD = −0.34 (95% CI: −0.67, −0.02), p < 0.05, PEDro =6.4 ± 0.45] and leptin [SMD = −0.92 (95% CI: −1.28, −0.57), p < 0.00001, PEDro = 6.2 ± 0.75].

Discussion: This systematic review revealed that exercise and physical activity may modulate resting hunger and satiety in older adults. Decreases in fasting leptin and glucose hormones suggest that exercise promotes satiety sensitivity in adults aged 60+. This review highlights that engaging in exercise and activity programs may provide a meaningful avenue for improving chronic and functional disease burden in later life by promoting appetite control and balanced energy intake. Recommendations for future research include investigations of appetite in response to varied exercise modalities within more diverse and representative samples of older adults.

Physical Activity and Bone Health: What Is the Role of Immune System? A Narrative Review of the Third Way

Bone tissue can be seen as a physiological hub of several stimuli of different origin (e.g., dietary, endocrine, nervous, immune, skeletal muscle traction, biomechanical load). Their integration, at the bone level, results in: (i) changes in mineral and protein composition and microarchitecture and, consequently, in shape and strength; (ii) modulation of calcium and phosphorous release into the bloodstream, (iii) expression and release of hormones and mediators able to communicate the current bone status to the rest of the body. Different stimuli are able to act on either one or, as usual, more levels. Physical activity is the key stimulus for bone metabolism acting in two ways: through the biomechanical load which resolves into a direct stimulation of the segment(s) involved and through an indirect load mediated by muscle traction onto the bone, which is the main physiological stimulus for bone formation, and the endocrine stimulation which causes homeostatic adaptation. The third way, in which physical activity is able to modify bone functions, passes through the immune system. It is known that immune function is modulated by physical activity; however, two recent insights have shed new light on this modulation. The first relies on the discovery of inflammasomes, receptors/sensors of the innate immunity that regulate caspase-1 activation and are, hence, the tissue triggers of inflammation in response to infections and/or stressors. The second relies on the ability of certain tissues, and particularly skeletal muscle and adipose tissue, to synthesize and secrete mediators (namely, myokines and adipokines) able to affect, profoundly, the immune function. Physical activity is known to act on both these mechanisms and, hence, its effects on bone are also mediated by the immune system activation. Indeed, that immune system and bone are tightly connected and inflammation is pivotal in determining the bone metabolic status is well-known. The aim of this narrative review is to give a complete view of the exercise-dependent immune system-mediated effects on bone metabolism and function.

Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies

The prevalence of obesity in combination with sarcopenia (the age-related loss of muscle mass and strength or physical function) is increasing in adults aged 65 years and older. A major subset of adults over the age of 65 is now classified as having sarcopenic obesity, a high-risk geriatric syndrome predominantly observed in an ageing population that is at risk of synergistic complications from both sarcopenia and obesity. This Review discusses pathways and mechanisms leading to muscle impairment in older adults with obesity. We explore sex-specific hormonal changes, inflammatory pathways and myocellular mechanisms leading to the development of sarcopenic obesity. We discuss the evolution, controversies and challenges in defining sarcopenic obesity and present current body composition modalities used to assess this condition. Epidemiological surveys form the basis of defining its prevalence and consequences beyond comorbidity and mortality. Current treatment strategies, and the evidence supporting them, are outlined, with a focus on calorie restriction, protein supplementation and aerobic and resistance exercises. We also describe weight loss-induced complications in patients with sarcopenic obesity that are relevant to clinical management. Finally, we review novel and potential future therapies including testosterone, selective androgen receptor modulators, myostatin inhibitors, ghrelin analogues, vitamin K and mesenchymal stem cell therapy.

High intensity, circuit-type integrated neuromuscular training alters energy balance and reduces body mass and fat in obese women: A 10-month training-detraining randomized controlled trial

This randomized controlled trial examined body mass, body composition, energy balance and performance responses of previously sedentary overweight/obese women to a circuit-type integrated neuromuscular training program with alternative modalities. Forty-nine healthy overweight or class I obese females (36.4±4.4 yrs) were randomly assigned to either a control (N = 21), training (N = 14) or training-detraining (N = 14) group. In weeks 1-20, the training groups trained three times/week using 10-12 whole-body exercises of progressively increased intensity/volume, organized in timed interval circuit form. In weeks 21-40, the training group continued training whereas the training-detraining group not. Heart rate, perceived exertion, blood lactate, exertion, oxygen consumption and excess post-exercise oxygen consumption were measured for one session/phase/person and exercise energy expenditure was calculated. Energy intake, habitual physical activity, resting metabolic rate, body composition, body mass, strength and maximal oxygen consumption were measured at baseline, mid-intervention and post-intervention. A two-way repeated measures ANOVA was used to determine differences between three time points and three groups. In C, VO2max declined (p<0.013) and body fat (p<0.008), waist (p<0.059) and hip (p<0.012) circumferences increased after 40 weeks compared to baseline. Training reduced body mass (6%, p<0.001), body fat (~5.5%, p<0.001) and increased fat-free mass (1.2-3.4%, p<0.05), strength (27.2%, p<0.001) and endurance (26.8%, p<0.001) after a 10-month implementation period using a metabolic overload of only 5-12 metabolic equivalents of task-hours per week. Training induced a long-term negative energy balance during an exercise and a non-exercise day due to an elevation of resting metabolic rate (6%-10%, p<0.05) and exercise-related energy expenditure. Training had an 8% and 94% attrition and attendance rates, respectively. Training-induced gains were attenuated but not lost following a 5-month detraining. A 10-month implementation of a high-intensity interval type training program elicited both endurance and musculoskeletal gains and resulted in a long-term negative energy balance that induced a progressive and sustained reduction of body and fat mass.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03134781.

Post-Game High Protein Intake May Improve Recovery of Football-Specific Performance during a Congested Game Fixture: Results from the PRO-FOOTBALL Study

The effects of protein supplementation on performance recovery and inflammatory responses during a simulated one-week in-season microcycle with two games (G1, G2) performed three days apart were examined. Twenty football players participated in two trials, receiving either milk protein concentrate (1.15 and 0.26 g/kg on game and training days, respectively) (PRO) or an energy-matched placebo (1.37 and 0.31 g/kg of carbohydrate on game and training days, respectively) (PLA) according to a randomized, repeated-measures, crossover, double-blind design. Each trial included two games and four daily practices. Speed, jump height, isokinetic peak torque, and muscle soreness of knee flexors (KF) and extensors (KE) were measured before G1 and daily thereafter for six days. Blood was drawn before G1 and daily thereafter. Football-specific locomotor activity and heart rate were monitored using GPS technology during games and practices. The two games resulted in reduced speed (by 3–17%), strength of knee flexors (by 12–23%), and jumping performance (by 3–10%) throughout recovery, in both trials. Average heart rate and total distance covered during games remained unchanged in PRO but not in PLA. Moreover, PRO resulted in a change of smaller magnitude in high-intensity running at the end of G2 (75–90 min vs. 0–15 min) compared to PLA (P = 0.012). KE concentric strength demonstrated a more prolonged decline in PLA (days 1 and 2 after G1, P = 0.014–0.018; days 1, 2 and 3 after G2, P = 0.016–0.037) compared to PRO (days 1 after G1, P = 0.013; days 1 and 2 after G2, P = 0.014–0.033) following both games. KF eccentric strength decreased throughout recovery after G1 (PLA: P=0.001–0.047—PRO: P =0.004–0.22) in both trials, whereas after G2 it declined throughout recovery in PLA (P = 0.000–0.013) but only during the first two days (P = 0.000–0.014) in PRO. No treatment effect was observed for delayed onset of muscle soreness, leukocyte counts, and creatine kinase activity. PRO resulted in a faster recovery of protein and lipid peroxidation markers after both games. Reduced glutathione demonstrated a more short-lived reduction after G2 in PRO compared to PLA. In summary, these results provide evidence that protein feeding may more efficiently restore football-specific performance and strength and provide antioxidant protection during a congested game fixture.

Inflammation status of healthy young men: initial and specific responses to resistance training

Our primary aim was to study the effects of a 4-week preparatory resistance-training (RT) period followed by 12 weeks of 2 specific RT protocols (either hypertrophic-strength (HS) or strength-hypertrophy-power training) on inflammation markers and the possible relationship of the changes in abdominal fat and lean mass to the changes in inflammation status. A total of 82 healthy men were included in the study. Maximal concentric leg press strength (1-repetition maximum), total body lean mass, total body and abdominal fat mass, circulating high-sensitivity C-reactive protein, interleukin-6, interleukin-1 receptor antagonist (IL-1ra), monocyte chemoattractant protein 1 (MCP-1), and selected adipocytokines (resistin, adiponectin, and leptin) concentrations were measured before and after 4 (wk4) and 16 weeks (wk16) of RT. After the initial phase of RT, on wk4, abdominal and total fat mass as well as plasma leptin concentrations were significantly reduced (p < 0.05), whereas muscle mass, IL-1ra, resistin, and MCP-1 concentrations were significantly increased (p < 0.05). During specialized training phase, at wk16, only HS led to further reduction in abdominal and total fat mass, resistin, and leptin (p < 0.05), whereas both training modes led to lower MCP-1 concentrations (p < 0.05). Abdominal fat mass and circulating leptin were reduced already after 4 weeks of RT. Simultaneously, circulating MCP-1 and resistin concentrations increased, possibly as markers of muscle adaptation and regeneration. The present findings also suggest that RT with hypertrophic focus is beneficial for further reductions in abdominal fat mass and to decrease circulating inflammatory markers.

Resistance training prevents the cardiovascular changes caused by high-fat diet

AIMS

Aerobic exercise is indicated for prevention and treatment of obesity-induced cardiovascular disorders. Although the resistance training (RT) may also produce effects similar to aerobic exercise, this is not completely clear yet. In the present study, we tested if RT in moderate intensity might prevent alterations in blood pressure (BP), sympathetic modulation of systolic blood pressure (SBP), baroreflex function and the changes in renin-angiotensin system (RAS) and cytokines mRNA expression within the nucleus of the tract solitary (NTS) in rats fed with high-fat diet (HFD).

MAIN METHODS

Male Holtzman rats (300-320 g) were divided into 4 groups: sedentary with standard chow diet (SED-SD); sedentary with high-fat diet (SED-HFD); RT with standard chow diet (RT-SD); and RT with high-fat diet (RT-HFD). The trained groups performed a total of 10 weeks of moderate intensity RT in a vertical ladder. In the first 3 weeks all experimental groups were fed with SD. In the next 7 weeks, the SED-HFD and RT-HFD groups were fed with HFD.

KEY FINDINGS

In SED-HFD, BP and sympathetic modulation of SBP increased, whereas baroreflex bradycardic responses were attenuated. RT prevented the cardiovascular and inflammatory responses (increases in tumoral necrosis factor-α and interleukin-1β) produced by HFD in SED rats. The anti-inflammatory interleukin-10, angiotensin type 2 receptor, Mas receptor and angiotensin converting enzyme 2 mRNA expressions in the NTS increased in the RT-HFD compared to SED-HFD.

SIGNIFICANCE

The data demonstrated that moderate intensity RT prevented obesity-induced cardiovascular disorders simultaneously with reduced inflammatory responses and modifications of RAS in the NTS.

Impact of Wheelchair Rugby on Body Composition of Subjects With Tetraplegia: A Pilot Study

OBJECTIVE

To investigate the longitudinal effects of wheelchair rugby (WR) training on body composition of subjects with tetraplegia.

DESIGN

Subjects were evaluated at baseline and after WR training.

SETTING

Faculty of physical education settings.

PARTICIPANTS

Individuals with tetraplegia (N=13; age, 26.6±6.0y).

INTERVENTIONS

Four sessions per week of WR training composed by aerobic and anaerobic activities and technical and tactical aspects of WR. The average time of intervention was 8.1±2.5 months.

MAIN OUTCOME MEASURES

Body composition assessed by dual-energy x-ray absorptiometry.

RESULTS

After training, fat mass was significantly reduced in the whole body (15,191±4603 vs 13,212±3318 g, P=.016), trunk (7058±2639 vs 5693±1498 g, P=.012), and legs (2847±817 vs 2534±742 g, P=.003). Conversely, increased bone mineral content (183±35 vs 195±32 g, P=.01) and fat-free mass (2991±549 vs 3332±602 g, P=.016) in the arms and reduced bone mineral content in the trunk (553±82 vs 521±86 g, P=.034) were observed after training. Furthermore, no significant correlation between the duration of training and changes in body composition was detected.

CONCLUSIONS

Regular WR training increased lean mass and bone mineral content in the arms and decreased total body fat mass. Conversely, WR training was associated with decreased bone mineral content in the trunk. These results suggest that regular WR training improves body composition in subjects with tetraplegia.

Pilot study on the effects of a 2-week hiking vacation at moderate versus low altitude on plasma parameters of carbohydrate and lipid metabolism in patients with metabolic syndrome

Background

Hypoxic and hypobaric conditions may augment the beneficial influence of training on cardiovascular risk factors. This pilot study aimed to explore for effects of a two-week hiking vacation at moderate versus low altitude on adipokines and parameters of carbohydrate and lipid metabolism in patients with metabolic syndrome.

Methods

Fourteen subjects (mean age: 55.8 years, range: 39 – 69) with metabolic syndrome participated in a 2-week structured training program (3 hours of guided daily hiking 4 times a week, training intensity at 55-65% of individual maximal heart rate; total training time, 24 hours). Participants were divided for residence and training into two groups, one at moderate altitude (1,900 m; n = 8), and the other at low altitude (300 m; n = 6). Anthropometric, cardiovascular and metabolic parameters were measured before and after the training period.

Results

In study participants, training overall reduced circulating levels of total cholesterol (p = 0.024), low-density lipoprotein cholesterol (p = 0.025) and adiponectin (p < 0.001). In the group training at moderate altitude (n = 8), lowering effects on circulating levels were significant not only for total cholesterol, low-density-lipoprotein cholesterol and adiponectin (all, p < 0.05) but also for triglycerides (p = 0.025) and leptin (p = 0.015), whereas in the low altitude group (n = 6), none of the lipid parameters was significantly changed (each p > 0.05). Hiking-induced relative changes of triglyceride levels were positively associated with reductions in leptin levels (p = 0.006). As compared to 300 m altitude, training at 1,900 m showed borderline significant differences in the pre-post mean reduction rates of triglyceride (p = 0.050) and leptin levels (p = 0.093).

Conclusions

Preliminary data on patients with metabolic syndrome suggest that a 2-week hiking vacation at moderate altitude may be more beneficial for adipokines and parameters of lipid metabolism than training at low altitude. In order to draw firm conclusions regarding better corrections of dyslipidemia and metabolic syndrome by physical exercise under mild hypobaric and hypoxic conditions, a sufficiently powered randomized clinical trial appears warranted.

Trial registration

ClinicalTrials.gov ID NCT02013947 (first received November 6, 2013).

Nutrition and protein energy homeostasis in elderly

Protein-energy homeostasis is a major determinant of healthy aging. Inadequate nutritional intakes and physical activity, together with endocrine disturbances are associated with of sarcopenia and frailty. Guidelines from scientific societies mainly address the quantitative aspects of protein and energy nutrition in elderly. Besides these quantitative aspects of protein load, perspective strategies to promote muscle protein synthesis and prevent sarcopenia include pulse feeding, the use of fast proteins and the addition of leucine or citrulline to dietary protein. An integrated management of sarcopenia, taking into account the determinants of muscle wasting, i.e. nutrition, physical activity, anabolic factors such as androgens, vitamin D and n-3 polyunsaturated fatty acids status, needs to be tested in the prevention and treatment of sarcopenia. The importance of physical activity, specifically resistance training, is emphasized, not only in order to facilitate muscle protein anabolism but also to increase appetite and food intake in elderly people at risk of malnutrition. According to present data, healthy nutrition in elderly should respect the guidelines for protein and energy requirement, privilege a Mediterranean way of alimentation, and be associated with a regular physical activity. Further issues relate to the identification of the genetics determinants of protein energy wasting in elderly.

Circulatory and Adipose Tissue Leptin and Adiponectin in Relationship to Resting Energy Expenditure in Patients With Chronic Obstructive Pulmonary Disease

Increases in resting energy expenditure (REE) likely contribute to weight loss in various chronic diseases. In chronic obstructive pulmonary disease (COPD), relationships between the ventilatory impairment and increased REE, and between disturbances in adipokines and weight loss were previously described. Therefore, we investigated serum levels and adipose tissue expression of leptin and adiponectin, and their relationships to REE in patients with COPD. In 44 patients with stable COPD (38 male; age 62.3±7.2 years), REE was assessed using indirect calorimetry. Subcutaneous adipose tissue samples were analyzed using real-time PCR. From underweight [n=9; body mass index (BMI) <20.0 kg.m−2], to normal weight-overweight (n=24, BMI=20.0-29.9 kg.m−2) and obese patients (n=11; BMI≥30 kg.m−2), REE adjusted for body weight decreased (32.9±6.1 vs. 26.2±5.8 vs. 23.9±6.6 kcal.kg−1.24 h−1, p=0.006), serum levels and adipose tissue expression of leptin increased (p<0.001 for both), and serum and adipose tissue adiponectin decreased (p<0.001; p=0.004, respectively). REE was inversely related to serum and adipose tissue leptin (R=−0.547, p<0.001; R=−0.458, p=0.002), and directly to serum adiponectin (R=0.316, p=0.039). Underweight patients had increased REE compared to normal weight-overweight patients, in association with reductions in serum and adipose tissue leptin, and increased serum adiponectin, suggesting a role of adipokines in energy imbalance in COPD-related cachexia.

Stress in obesity and associated metabolic and cardiovascular disorders

Obesity has significant implications for healthcare, since it is a major risk factor for both type 2 diabetes and the metabolic syndrome. This syndrome is a common and complex disorder combining obesity, dyslipidemia, hypertension, and insulin resistance. It is associated with high atherosclerotic cardiovascular risk, which can only partially be explained by its components. Therefore, to explain how obesity contributes to the development of metabolic and cardiovascular disorders, more and better insight is required into the effects of personal and environmental stress on disease processes. In this paper, we show that obesity is a chronic inflammatory disease, which has many molecular mechanisms in common with atherosclerosis. Furthermore, we focus on the role of oxidative stress associated with obesity in the development of the metabolic syndrome. We discuss how several stress conditions are related to inflammation and oxidative stress in association with obesity and its complications. We also emphasize the relation between stress conditions and the deregulation of epigenetic control mechanisms by means of microRNAs and show how this impairment further contributes to the development of obesity, closing the vicious circle. Finally, we discuss the limitations of current anti-inflammation and antioxidant therapy to treat obesity.

The effect of acute exercise on undercarboxylated osteocalcin in obese men

SUMMARY

The purpose of this study was to examine if the reduction in glucose post-exercise is mediated by undercarboxylated osteocalcin (unOC). Obese men were randomly assigned to do aerobic or power exercises. The change in unOC levels was correlated with the change in glucose levels post-exercise. The reduction in glucose post-acute exercise may be partly related to increased unOC.

INTRODUCTION

Osteocalcin (OC) in its undercarboxylated (unOC) form may contribute to the regulation of glucose homeostasis. As exercise reduces serum glucose and improves insulin sensitivity in obese individuals and individuals with type 2 diabetes (T2DM), we hypothesised that this benefit was partly mediated by unOC.

METHODS

Twenty-eight middle-aged (52.4 ± 1.2 years, mean ± SEM), obese (BMI = 32.1 ± 0.9 kg m(-2)) men were randomly assigned to do either 45 min of aerobic (cycling at 75% of VO(2peak)) or power (leg press at 75% of one repetition maximum plus jumping sequence) exercises. Blood samples were taken at baseline and up to 2 h post-exercise.

RESULTS

At baseline, unOC was negatively correlated with glucose levels (r = -0.53, p = 0.003) and glycosylated haemoglobin (HbA1c) (r = -0.37, p = 0.035). Both aerobic and power exercises reduced serum glucose (from 7.4 ± 1.2 to 5.1 ± 0.5 mmol L(-1), p = 0.01 and 8.5 ± 1.2 to 6.0 ± 0.6 mmol L(-1), p = 0.01, respectively). Aerobic exercise significantly increased OC, unOC and high-molecular-weight adiponectin, while power exercise had a limited effect on OC and unOC. Overall, those with higher baseline glucose and HbA1c had greater reductions in glucose levels after exercise (r = -0.46, p = 0.013 and r = -0.43, p = 0.019, respectively). In a sub-group of obese people with T2DM, the percentage change in unOC levels was correlated with the percentage change in glucose levels post-exercise (r = -0.51, p = 0.038).

CONCLUSIONS

This study reports that the reduction in serum glucose post-acute exercise (especially aerobic exercise) may be partly related to increased unOC.

Aging, resistance training, and diabetes prevention

With the aging of the baby-boom generation and increases in life expectancy, the American population is growing older. Aging is associated with adverse changes in glucose tolerance and increased risk of diabetes; the increasing prevalence of diabetes among older adults suggests a clear need for effective diabetes prevention approaches for this population. The purpose of paper is to review what is known about changes in glucose tolerance with advancing age and the potential utility of resistance training (RT) as an intervention to prevent diabetes among middle-aged and older adults. Age-related factors contributing to glucose intolerance, which may be improved with RT, include improvements in insulin signaling defects, reductions in tumor necrosis factor-α, increases in adiponectin and insulin-like growth factor-1 concentrations, and reductions in total and abdominal visceral fat. Current RT recommendations and future areas for investigation are presented.

Making fat work

The burgeoning obesity and metabolic disease epidemics in the developed world are exerting a terrible toll on society, yet the precise mechanisms responsible for the emergence of these dramatic trends over a relatively short period of time remain poorly understood. Philip A.Wood's book How Fat Works provides important insights into cellular lipid metabolism, as well as discussing some of the important external contributors to the development of human obesity. The foundation provided by this book allows for the exploration of how body fat has gone from hero during the millennia when starvation was the paramount nutritional risk to its current role as villain in our period of caloric excess. With the incredible personal and societal costs brought about by excess body weight, a comprehensive understanding of the mechanisms responsible for obesity is fundamentally necessary if we are to reverse these dire trends. Here, we delve deeper into some of the forces contributing to the obesity epidemic and discuss some individual measures as well as public policy decisions that may help reverse weight trends, while specifically focusing on the growing problem of pediatric obesity.