Cross-sectional interactive associations of physical activity and sedentary behaviour with physical capacity across adulthood

BACKGROUND

The way physical activity (PA) and sedentary behaviour (SB) independently and interactively modify the age-related decline in physical capacity remains poorly understood. This cross-sectional study investigated the independent and interactive associations of PA and SB with physical function and performance throughout the adult life course.

METHODS

Data from 499 community-dwelling adults (63% female) aged 20-92 years, involved in the INSPIRE Human Translational Cohort, were used in this cross-sectional study. Daily time spent on moderate-to-vigorous PA (MVPA, min/day) and SB (h/day) was measured with activPAL triaxial accelerometers. Physical function and performance were assessed through the measurement of the 4-m usual gait speed (m/s), handgrip strength (kg), lower-limb strength (isokinetic knee extension torque, N·m), estimated lower-limb power (five-time chair-rise test performance, s) and cardiorespiratory fitness (V̇O2max, mL/kg/min). Confounder-adjusted multiple linear and curvilinear regressions were performed to investigate how MVPA, SB and their interactions were associated with the physical outcomes (all square root-transformed except gait speed) throughout the adulthood spectrum.

RESULTS

Interaction analyses revealed that the combination of higher levels of MVPA with lower levels of SB favourably reshaped the negative relationship between handgrip strength and age (age2 × SB × MVPA: B = -7E-08, SE = 3E-08, P < 0.05). In addition, higher levels of MVPA were independently associated with an improved age-related profile in gait speed (age2 × MVPA: B = 3E-06, SE = 1E-06, P < 0.05), chair-rise performance (age × MVPA: B = -9E-05, SE = 4E-05, P < 0.05) and V̇O2max (MVPA at 21 years: B = 3E-02, SE = 7E-03, P < 0.05; age × MVPA: B = -5E-04, SE = 2E-04, P < 0.05). Conversely, the detrimental association of age with lower-limb muscle strength (age × SB: B = -1E-04, SE = 6E-05, P < 0.05) and chair-rise performance (age × SB: B = 1E-05, SE = 7E-06, P < 0.05) was exacerbated with increasing duration of SB, independently of MVPA. Supplementary analyses further revealed that some of these associations were age and sex specific.

CONCLUSIONS

This cross-sectional study demonstrated that reduced sedentary time and increased activity duration were independently and synergistically associated with an attenuated age-related loss in physical capacity. These findings need to be confirmed with longitudinal data but encourage both adopting an active lifestyle and reducing sedentary time as preventive measures against physical aging.

The Impact of COVID-19 on the Response to Hypoxia

Louis, Alexandre, Charlotte Pröpper, Yann Savina, Corentin Tanne, Guy Duperrex, Paul Robach, Pascal Zellner, Stéphane Doutreleau, Jean-Michel Boulet, Alain Frey, Fabien Pillard, Cristina Pistea, Mathias Poussel, Thomas Thuet, Jean-Paul Richalet, and François Lecoq-Jammes. The impact of COVID-19 on the response to hypoxia. High Alt Med Biol. 24:321-328, 2023. Background: Severe high-altitude illness (SHAI) and coronavirus disease 2019 (COVID-19), while differing in most aspects of pathophysiology, both involve respiratory capacity. We examined the long-term impact of COVID-19 on response to hypoxia in individuals free of symptoms but having tested positive during the pandemic. The need for recommendations for such individuals planning a stay at high altitude are discussed. Methods: This multicenter study recruited participants from the multiSHAI cohort, all of whom had previously undergone a hypoxic exercise test. These participants were classified into two groups depending on whether they had since suffered mild-to-moderate COVID-19 (COVID+) or not (Control) and then asked to retake the test. Primary outcomes were: desaturation induced by hypoxia at exercise (ΔSpE), hypoxic cardiac response at exercise, hypoxic ventilatory response at exercise, and SHAI risk score. Results: A total of 68 participants retook the test, 36 classified in the COVID+ group. Analyses of primary outcomes showed no significant differences between groups. However, the COVID+ group showed significantly increased ventilation (VE) parameters during both hypoxic (p = 0.003) and normoxic exercise (p = 0.007). However, only the VE/oxygen consumption relationship during hypoxic exercise was significantly different. Conclusion: This study demonstrates no negative impact of COVID-19 on response to hypoxia as evaluated by the Richalet test. Clinical Trial Registration: NTC number: NCT05167357.

Validation of a Score for the Detection of Subjects with High Risk for Severe High-Altitude Illness

PURPOSE

A decision tree based on a clinicophysiological score (severe high-altitude illness (SHAI) score) has been developed to detect subjects susceptible to SHAI. We aimed to validate this decision tree, to rationalize the prescription of acetazolamide (ACZ), and to specify the rule for a progressive acclimatization.

METHODS

Data were obtained from 641 subjects in 15 European medical centers before and during a sojourn at high altitude. Depending on the value of the SHAI score, advice was given and ACZ was eventually prescribed. The outcome was the occurrence of SHAI at high altitude as a function of the SHAI score, ACZ prescription, and use and fulfillment of the acclimatization rule.

RESULTS

The occurrence of SHAI was 22.6%, similar to what was observed 18 yr before (23.7%), whereas life-threatening forms of SHAI (high-altitude pulmonary and cerebral edema) were less frequent (2.6%-0.8%, P = 0.007). The negative predictive value of the decision tree based was 81%, suggesting that the procedure is efficient to detect subjects who will not suffer from SHAI, therefore limiting the use of ACZ. The maximal daily altitude gain that limits the occurrence of SHAI was established at 400 m. The occurrence of SHAI was reduced from 27% to 12% when the recommendations for ACZ use and 400-m daily altitude gain were respected (P < 0.001).

CONCLUSIONS

This multicenter study confirmed the interest of the SHAI score in predicting the individual risk for SHAI. The conditions for an optimized acclimatization (400-m rule) were also specified, and we proposed a rational decision tree for the prescription of ACZ, adapted to each individual tolerance to hypoxia.

What Is the Impact of Physical Effort on the Diagnosis of Concussion?

OBJECTIVE

Sport-related concussion commonly occurs in contact sports such as rugby. To date, diagnosis is based on the realization of clinical tests conducted pitch-side. Yet, the potential effect of prior physical effort on the results of these tests remains poorly understood. The purpose of this study was to determine whether preceding physical effort can influence the outcome of concussion assessments.

DESIGN

Prospective observational study.

SETTING

University Medicine Center.

PATIENTS

A cohort of 40 subjects (20 rugby players and 20 athletes from a range of sports).

INTERVENTION

A concussion assessment was performed immediately after physical activity. After a period of 6 months and under the same experimental conditions, the same cohort performed the same tests in resting conditions.

MAIN OUTCOME MEASURES

Results of concussion tests.

RESULTS

In both cohorts, the comparison for postexercise and rest assessments demonstrated a most likely moderate-to-very large increase in the number of symptoms, severity of symptoms, and balance error scoring system score. In the rugby cohort, scores for concentration, delayed memory and standardized assessment of concussion (SAC), likely-to-most likely decreased following completion of physical activity compared with baseline values. The between-cohort comparison reported a most likely greater impact after exercise in the rugby players for delayed recall (0.73 ± 0.61) and SAC score (0.75 ± 0.41).

CONCLUSIONS

Physical activity altered the results of concussion diagnostic tests in athletes from a range of sports and notably in rugby players. Therefore, physical efforts before the concussion incident should be accounted for during pitch-side assessments and particularly during rugby competition and training.

The exerkine apelin reverses age-associated sarcopenia

Sarcopenia, the degenerative loss of skeletal muscle mass, quality and strength, lacks early diagnostic tools and new therapeutic strategies to prevent the frailty-to-disability transition often responsible for the medical institutionalization of elderly individuals. Herein we report that production of the endogenous peptide apelin, induced by muscle contraction, is reduced in an age-dependent manner in humans and rodents and is positively associated with the beneficial effects of exercise in older persons. Mice deficient in either apelin or its receptor (APLNR) presented dramatic alterations in muscle function with increasing age. Various strategies that restored apelin signaling during aging further demonstrated that this peptide considerably enhanced muscle function by triggering mitochondriogenesis, autophagy and anti-inflammatory pathways in myofibers as well as enhancing the regenerative capacity by targeting muscle stem cells. Taken together, these findings revealed positive regulatory feedback between physical activity, apelin and muscle function and identified apelin both as a tool for diagnosis of early sarcopenia and as the target of an innovative pharmacological strategy to prevent age-associated muscle weakness and restore physical autonomy.

Determination of Cardiac Output in Pulmonary Hypertension Using Impedance Cardiography

BACKGROUND

Cardiac output (CO) is a prognostic factor in pulmonary hypertension (PH). Right heart catheterisation using the direct Fick method or thermodilution (TD) is the reference technique for CO measurement. Impedance cardiography (IPc) is a known non-invasive method of measuring CO.

OBJECTIVES

In our study, we assume that the measurement of CO by IPc using the PHYSIOFLOW® system is as accurate as TD or using the direct Fick method in patients with PH in group 1 or group 4.

METHODS

A total of 75 patients were enrolled in a prospective study carried out at the hypertension reference centre of Toulouse University Hospital. Right heart catheterisation was performed for the diagnosis or follow-up of the disease. CO was measured using the Fick method, TD, and IPc simultaneously. A Bland-Altman analysis was plotted.

RESULTS

CO was 5.7 ± 1.9 L/min as measured by the Fick method, 5.4 ± 1.5 L/min by TD, and 5.5 ± 1.7 L/min by IPc. The bias between CO measurements by IPc and the direct Fick method was 0.149 L/min (95% CI, -0.298 to 0.596). The bias between CO measurements by IPc and the TD method was -0.153 L/min (95% CI, -0.450 to 0.153). The correlation decreased with the more extreme CO values (< 3 L/min or > 7 L/min). A few factors changed the agreement between measurements (BMI or membership in group 4).

CONCLUSION

To conclude, this study shows that the measurement of CO by IPc in PH patients is reliable compared to the direct Fick method and TD obtained by right heart catheterisation. This accuracy decreases for extreme CO values.

Isoprostanes as markers for muscle aging in older athletes

Introduction

Production of isoprostanes (IsoPs) is enhanced after acute, intense, and prolonged exercise, in untrained subjects. This effect is greater in older subjects. The present study aims to delineate the profile of acute-exercise-induced IsoPs levels in young and older endurance-trained subjects.

Methods

All included subjects were male, young (n = 6; 29 yrs ± 5.7) or older (n = 6; 63.7 yrs ± 2.3), and competitors. The kinetics of F₂-IsoPs in blood-sera was assessed at rest, for the maximal aerobic exercise power (MAP) corresponding to the cardio-respiratory fitness index and after a 30-min recovery period.

Results

No significant time effect on F₂-IsoPs kinetics was identified in young subjects. However, in older athletes, F₂-IsoPs blood-concentrations at the MAP were higher than at rest, whereas these blood-concentrations did not differ between rest and after the 30-min recovery period.

Conclusion

Because plasma glutathione (GSH) promotes the formation of some F₂-IsoPs, we suggest that the surprising decrease in F₂-IsoPs levels in older subjects would be caused by decreased GSH under major ROS production in older subjects. We argue that the assessment F₂-IsoPs in plasma as biomarkers of the aging process should be challenged by exercise to improve the assessment of the functional response against reactive oxygen species in older subjects.

•

Acute exercise promotes an increase in F₂-IsoPs plasma level in older athletes.

•

The F₂-IsoPs plasma level significantly decreased after recovery in older athletes.

•

This kinetic of F₂-IsoPs could reflect a decrease of glutathione (GSH).

•

Oxidative stress status determination should be challenged by exercise.

•

Assessment of F₂-IsoPs plasma level should be paired to GSH assessment.

Whole-body strength training with Huber Motion Lab and traditional strength training in cardiac rehabilitation: A randomized controlled study

BACKGROUND

Isometric strengthening has been rarely studied in patients with coronary heart disease (CHD), mainly because of possible potential side effects and lack of appropriate and reliable devices.

OBJECTIVE

We aimed to compare 2 different modes of resistance training, an isometric mode with the Huber Motion Lab (HML) and traditional strength training (TST), in CHD patients undergoing a cardiac rehabilitation program.

DESIGN

We randomly assigned 50 patients to HML or TST. Patients underwent complete blinded evaluation before and after the rehabilitation program, including testing for cardiopulmonary exercise, maximal isometric voluntary contraction, endothelial function and body composition.

RESULTS

After 4 weeks of training (16 sessions), the groups did not differ in body composition, anthropometric characteristics, or endothelial function. With HML, peak power output (P=0.035), maximal heart rate (P<0.01) and gain of force measured in the chest press position (P<0.02) were greater after versus before training.

CONCLUSION

Both protocols appeared to be well tolerated, safe and feasible for these CHD patients. A training protocol involving 6s phases of isometric contractions with 10s of passive recovery on an HML device could be safely implemented in rehabilitation programs for patients with CHD and improve functional outcomes.

Medical and pharmacological approach to adjust the salbutamol anti-doping policy in athletes

BACKGROUND

Salbutamol abuse detection by athletes is based on a urinary upper threshold defined by the World Anti-Doping Agency (WADA). However, this threshold was determined in healthy, untrained individuals and after a dose of salbutamol inhaled that might not really mirror the condition of asthmatic athletes and the experts's guidelines for asthma management. We aimed to revise this threshold in accordance with recommended clinical practice (that appear to be different from the actual WADA recommendation) and in exercise conditions.

METHODS

For the present open-label design study, we included 12 trained male cyclists (20 to 40 y/o) with asthma. Differently from the previous pharmacokinetic study supporting the actual salbutamol urinary upper threshold, we decided to administer a close to recommended clinical practice daily dose of 3x200 μg.d(-1) inhaled salbutamol (instead of 1600 μg.d(-1) as authorized by the anti-doping policy). Urine salbutamol concentration was quantified by liquid chromatography-tandem ion trap mass spectrometry and corrected for urine density, at rest and after a 90-min cycling effort at 70-80 % of the maximal aerobic power.

RESULTS

The maximum urine salbutamol concentration value peaked after the cycling effort and was 510 ng.mL(-1). That is twice lower than the actual WADA threshold to sanction salbutamol abuse, this "legal" threshold being based on pharmacokinetic data after a daily dose that is 8 fold the total dose sequentially administrated in our study. Considering its 95 % confidence interval, this threshold value could be more stringent.

CONCLUSION

By using conditions in accordance with the experts' clinical and safety guidelines for asthma management in athletes undergoing an intense exercise bout, our study suggests that the urine salbutamol concentration threshold could be lowered to redefine the rule supporting the decision to sanction an athlete for salbutamol abuse.

Exercise training for managing behavioral and psychological symptoms in people with dementia: A systematic review and meta-analysis

This systematic review and meta-analysis of randomized controlled trials assessed the effects of exercise on behavioral and psychological symptoms of dementia (BPSD, including depression) in people with dementia (PWD). Secondary outcomes for the effects of exercise were mortality and antipsychotic use. Twenty studies were included in this review (n=18 in the meta-analysis). Most studies used a multicomponent exercise training (n=13) as intervention; the control group was often a usual care (n=10) or a socially-active (n=8) group. Exercise did not reduce global levels of BPSD (n=4. Weighted mean difference -3.884; 95% CI -8.969-1.201; I(2)=69.4%). Exercise significantly reduced depression levels in PWD (n=7). Standardized mean difference -0.306; 95% CI -0.571 to -0.041; I(2)=46.8%); similar patterns were obtained in sensitivity analysis performed among studies with: institutionalized people (p=0.038), multicomponent training (p=0.056), social control group (p=0.08), and low risk of attrition bias (p=0.11). Exploratory analysis showed that the principal BPSD (other than depression) positively affected by exercise was aberrant motor behavior. Exercise had no effect on mortality. Data on antipsychotics were scarce. In conclusion, exercise reduces depression levels in PWD. Future studies should examine whether exercise reduces the use (and doses) of antipsychotics and other drugs often used to manage BPSD.

Effects of vitamin C, vitamin E, zinc gluconate, and selenomethionine supplementation on muscle function and oxidative stress biomarkers in patients with facioscapulohumeral dystrophy: a double-blind randomized controlled clinical trial

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disease characterized by progressive weakness and atrophy of specific skeletal muscles. As growing evidence suggests that oxidative stress may contribute to FSHD pathology, antioxidants that might modulate or delay oxidative insults could help in maintaining FSHD muscle function. Our primary objective was to test whether oral administration of vitamin C, vitamin E, zinc gluconate, and selenomethionine could improve the physical performance of patients with FSHD. Adult patients with FSHD (n=53) were enrolled at Montpellier University Hospital (France) in a randomized, double-blind, placebo-controlled pilot clinical trial. Patients were randomly assigned to receive 500 mg vitamin C, 400mg vitamin E, 25mg zinc gluconate and 200 μg selenomethionine (n=26), or matching placebo (n=27) once a day for 17 weeks. Primary outcomes were changes in the two-minute walking test (2-MWT), maximal voluntary contraction, and endurance limit time of the dominant and nondominant quadriceps (MVCQD, MVCQND, TlimQD, and TlimQND, respectively) after 17 weeks of treatment. Secondary outcomes were changes in the antioxidant status and oxidative stress markers. Although 2-MWT, MVCQ, and TlimQ were all significantly improved in the supplemented group at the end of the treatment compared to baseline, only MVCQ and TlimQ variations were significantly different between groups (MVCQD: P=0.011; MVCQND: P=0.004; TlimQD: P=0.028; TlimQND: P=0.011). Similarly, the vitamin C (P<0.001), vitamin E as α-tocopherol (P<0.001), vitamin C/vitamin E ratio (P=0.017), vitamin E γ/α ratio (P=0.022) and lipid peroxides (P<0.001) variations were significantly different between groups. In conclusion, vitamin E, vitamin C, zinc, and selenium supplementation has no significant effect on the 2-MWT, but improves MVCQ and TlimQ of both quadriceps by enhancing the antioxidant defenses and reducing oxidative stress. This trial was registered at clinicaltrials.gov (number: NCT01596803).

High response rate and improved exercise capacity and quality of life with a new regimen of darbepoetin alfa with or without filgrastim in lower-risk myelodysplastic syndromes: a phase II study by the GFM

Darbepoetin (DAR), with or without granulocyte colony-stimulating factor (G-CSF), has proved effective in treating anemia in patients with lower-risk myelodysplastic syndrome (MDS), but its effects on quality of life (QoL) and exercise functioning are less well established. In this phase II study (no. NCT00443339), lower-risk MDS patients with anemia and endogenous erythropoietin (EPO) level <500 IU/L received DAR 500 μg once every 2 weeks for 12 weeks, with G-CSF added at week 12 in non-responders. Physical performance was assessed with the 6-min walking test and, for fit patients, maximal oxygen consumption (VO2max). QoL was evaluated using SF-36 and FACT-An tests. In 99 patients, erythroid response rate according to IWG 2006 criteria was 48 and 56 % at 12 and 24 weeks, respectively. Addition of G-CSF rescued 22 % of non-responders. In 48 % of the responders, interval between darbepoetin injections could be increased for maintenance treatment. Serum EPO level was the only independent predictive factor of response at 12 weeks, and its most discriminant cutoff value was 100 IU/L. QoL and VO2max showed improvement over time in responders, compared with non-responders. With a median follow-up of 52 months, median response duration was not reached, and 3-year cumulative incidence of acute myeloid leukemia and overall survival (OS) was 14.5 and 70 %, respectively. Baseline transfusion dependence, International Prognostic Score System (IPSS), and Revised IPSS accurately predicted OS from treatment onset. Tolerance of darbepoetin was good. In conclusion, this regimen of darbepoetin every 2 weeks yielded high response rates and prolonged response duration. Objective improvement in exercise testing and in patient-reported QoL confirms the clinical relevance of anemia correction with erythropoiesis-stimulating agents.

Functional muscle impairment in facioscapulohumeral muscular dystrophy is correlated with oxidative stress and mitochondrial dysfunction

Facioscapulohumeral muscular dystrophy (FSHD), the most frequent muscular dystrophy, is an autosomal dominant disease. In most individuals with FSHD, symptoms are restricted to muscles of the face, arms, legs, and trunk. FSHD is genetically linked to contractions of the D4Z4 repeat array causing activation of several genes. One of these maps in the repeat itself and expresses the DUX4 (the double homeobox 4) transcription factor causing a gene deregulation cascade. In addition, analyses of the RNA or protein expression profiles in muscle have indicated deregulations in the oxidative stress response. Since oxidative stress affects peripheral muscle function, we investigated mitochondrial function and oxidative stress in skeletal muscle biopsies and blood samples from patients with FSHD and age-matched healthy controls, and evaluated their association with physical performances. We show that specifically, oxidative stress (lipid peroxidation and protein carbonylation), oxidative damage (lipofuscin accumulation), and antioxidant enzymes (catalase, copper-zinc-dependent superoxide dismutase, and glutathione reductase) were higher in FSHD than in control muscles. FSHD muscles also presented abnormal mitochondrial function (decreased cytochrome c oxidase activity and reduced ATP synthesis). In addition, the ratio between reduced (GSH) and oxidized glutathione (GSSG) was strongly decreased in all FSHD blood samples as a consequence of GSSG accumulation. Patients with FSHD also had reduced systemic antioxidative response molecules, such as low levels of zinc (a SOD cofactor), selenium (a GPx cofactor involved in the elimination of lipid peroxides), and vitamin C. Half of them had a low ratio of gamma/alpha tocopherol and higher ferritin concentrations. Both systemic oxidative stress and mitochondrial dysfunction were correlated with functional muscle impairment. Mitochondrial ATP production was significantly correlated with both quadriceps endurance (T(LimQ)) and maximal voluntary contraction (MVC(Q)) values (rho=0.79, P=0.003; rho=0.62, P=0.05, respectively). The plasma concentration of oxidized glutathione was negatively correlated with the T(LimQ), MVC(Q) values, and the 2-min walk distance (MWT) values (rho=-0.60, P=0.03; rho=-0.56, P=0.04; rho=-0.93, P<0.0001, respectively). Our data characterized oxidative stress in patients with FSHD and demonstrated a correlation with their peripheral skeletal muscle dysfunction. They suggest that antioxidants that might modulate or delay oxidative insult may be useful in maintaining FSHD muscle functions.

Decreased fat oxidation during exercise in severe obstructive sleep apnoea syndrome

AIM

To assess whether the severity of obstructive sleep apnoea syndrome (OSAS) is associated with altered fat oxidation (FO) during physical exercise in men with type 2 diabetes (T2DM) and/or the metabolic syndrome (MetS).

METHODS

A total of 105 consecutive overweight or/and T2DM male patients were hospitalized for metabolic check-ups including bioimpedancemetry to measure lean body mass (LBM), standardized exercise calorimetry to assess FO, maximum fat oxidation (MFO) and carbohydrate oxidation (CHO), and OSAS screening using respiratory polygraphy. Twenty patients were classified as having severe OSAS, according to the apnoea/hypopnoea index (AHI), with greater than 30 events/h (mean AHI: 45.2±14.3 events/h). They were group-matched for age, BMI, and the presence of T2DM and/or MetS with two other OSAS groups: mild (AHI<15 events/h [n=20]; mean AHI: 8.8±4.5 events/h); and moderate (AHI>15 events/h and<30 events/h [n=20]; mean AHI: 23.7±4.2 events/h).

RESULTS

MFO adjusted for LBM was severely decreased in the severe OSAS group (1.6±1.0 mg.min(-1).kgLM(-1)) compared with the moderate (2.5±0.9 mg.min(-1).kgLM(-1); P=0.008) and mild (2.9±0.8 mg.min(-1).kgLM(-1); P=0.003) groups. All exercise-intensity levels (20%, 30%, 40% and 60% of the theoretical maximum aerobic power) showed reduced FO levels between the severe and mild-to-moderate OSAS groups. However, no differences in CHO were seen at any level of exercise between groups. Pearson's correlation analysis showed that AHI and the oxygen desaturation index were negatively associated with MFO corrected for LBM (r=0.41 and r=0.37, respectively; P<0.005).

CONCLUSION

OSAS severity is associated with altered FO during exercise.

The interest of gait markers in the identification of subgroups among fibromyalgia patients

BACKGROUND

Fibromyalgia (FM) is a heterogeneous syndrome and its classification into subgroups calls for broad-based discussion. FM subgrouping, which aims to adapt treatment according to different subgroups, relies in part, on psychological and cognitive dysfunctions. Since motor control of gait is closely related to cognitive function, we hypothesized that gait markers could be of interest in the identification of FM patients' subgroups. This controlled study aimed at characterizing gait disorders in FM, and subgrouping FM patients according to gait markers such as stride frequency (SF), stride regularity (SR), and cranio-caudal power (CCP) which measures kinesia.

METHODS

A multicentre, observational open trial enrolled patients with primary FM (44.1 ± 8.1 y), and matched controls (44.1 ± 7.3 y). Outcome measurements and gait analyses were available for 52 pairs. A 3-step statistical analysis was carried out. A preliminary single blind analysis using k-means cluster was performed as an initial validation of gait markers. Then in order to quantify FM patients according to psychometric and gait variables an open descriptive analysis comparing patients and controls were made, and correlations between gait variables and main outcomes were calculated. Finally using cluster analysis, we described subgroups for each gait variable and looked for significant differences in self-reported assessments.

RESULTS

SF was the most discriminating gait variable (73% of patients and controls). SF, SR, and CCP were different between patients and controls. There was a non-significant association between SF, FIQ and physical components from Short-Form 36 (p = 0.06). SR was correlated to FIQ (p = 0.01) and catastrophizing (p = 0.05) while CCP was correlated to pain (p = 0.01). The SF cluster identified 3 subgroups with a particular one characterized by normal SF, low pain, high activity and hyperkinesia. The SR cluster identified 2 distinct subgroups: the one with a reduced SR was distinguished by high FIQ, poor coping and altered affective status.

CONCLUSION

Gait analysis may provide additional information in the identification of subgroups among fibromyalgia patients. Gait analysis provided relevant information about physical and cognitive status, and pain behavior. Further studies are needed to better understand gait analysis implications in FM.

Physical activity and sarcopenia

Physical activity can be a valuable countermeasure to sarcopenia in its treatment and prevention. In considering physical training strategies for sarcopenic subjects, it is critical to consider personal and environmental obstacles to access opportunities for physical activity for any patient with chronic disease. This article presents an overview of current knowledge of the effects of physical training on muscle function and the physical activity recommended for sarcopenic patients. So that this countermeasure strategy can be applied in practice, the authors propose a standardized protocol for prescribing physical activity in chronic diseases such as sarcopenia.

Lipid oxidation in overweight men after exercise and food intake

Fat oxidation (FO) is optimized during low- to moderate-intensity exercise in lean and obese subjects, whereas high-intensity exercise induces preferential FO during the recovery period. After food intake during the postexercise period, it is unknown if FO differs according to the intensity exercise in overweight subjects. Fat oxidation was thus evaluated in overweight men after low- and high-intensity exercise during the recovery period before and after food intake as well as during a control session. Ten healthy, sedentary, overweight men (age, 27.9 +/- 5.6 years; body mass index, 27.8 +/- 1.3 kg m(-2); maximal oxygen consumption, 37 +/- 3.9 mL min(-1) kg(-1)) exercised on a cycloergometer (energy expenditure = 300 kcal) at 35% (E35) or 70% (E70) maximal oxygen consumption or rested (Cont). The subjects were fed 30 minutes after the exercise with 300 kcal (1256 kJ) more energy in the exercise sessions than in the Cont session. Respiratory quotient and FO were calculated by indirect calorimetry. Blood samples were analyzed to measure plasma glycerol, nonesterified fatty acid, glucose, and insulin. During exercise, mean respiratory quotient was lower (P < .05) and FO was higher (P < .01) in the E35 than in the E70 session (FO [in mg min(-1)]: E35 = 290 +/- 12, E70 = 256 +/- 38, and Cont = 131 +/- 7). Conversely, FO was higher in the E70 than in both the E35 session and the Cont session during the immediate recovery as well as during the postprandial recovery period (P = .005 for all; FO from the end of the exercise to the end of the session [in grams]: E70 = 45.7 +/- 8.9, E35 = 38.2 +/- 6.8, and Cont = 36.0 +/- 4.3). Blood parameters did not differ between the 3 sessions but changed according to the absorption of the nutrients. In overweight subjects, high-intensity exercise increased FO during the postexercise period even after food intake compared with the low-intensity exercise and the control session.

Validated treatments and therapeutic perspectives regarding physical activities

Current knowledge on physical activity in regard to sarcopenia is reported in this manuscript. The consequences of inactivity on muscle mass and function are discussed. Impact of resistance training on muscle and mass and function as well as its interaction with other factors associated with sarcopenia such as denervation, hormones modification and protein intake will be discussed.

Exercise-induced lipid mobilization in subcutaneous adipose tissue is mainly related to natriuretic peptides in overweight men

Involvement of sympathetic nervous system and natriuretic peptides in the control of exercise-induced lipid mobilization was compared in overweight and lean men. Lipid mobilization was determined using local microdialysis during exercise. Subjects performed 35-min exercise bouts at 60% of their maximal oxygen consumption under placebo or after oral tertatolol [a beta-adrenergic receptor (AR) antagonist]. Under placebo, exercise increased dialysate glycerol concentration (DGC) in both groups. Phentolamine (alpha-AR antagonist) potentiated exercise-induced lipolysis in overweight but not in lean subjects; the alpha(2)-antilipolytic effect was only functional in overweight men. After tertatolol administration, the DGC increased similarly during exercise no matter which was used probe in both groups. Compared with the control probe under placebo, lipolysis was reduced in lean but not in overweight men treated with the beta-AR blocker. Tertatolol reduced plasma nonesterified fatty acids and insulin concentration in both groups at rest. Under placebo or tertatolol, the exercise-induced changes in plasma nonesterified fatty acids, glycerol, and insulin concentrations were similar in both groups. Exercise promoted a higher increase in catecholamine and ANP plasma levels after tertatolol administration. In conclusion, the major finding of our study is that in overweight men, in addition to an increased alpha(2)-antilipolytic effect, the lipid mobilization in subcutaneous adipose tissue that persists during exercise under beta-blockade is not dependent on catecholamine action. On the basis of correlation findings, it seems to be related to a concomitant exercise-induced rise in plasma ANP when exercise is performed under tertatolol intake and a decrease in plasma insulin.

Sarcopenia: its assessment, etiology, pathogenesis, consequences and future perspectives

Sarcopenia is a loss of muscle protein mass and loss of muscle function. It occurs with increasing age, being a major component in the development of frailty. Current knowledge on its assessment, etiology, pathogenesis, consequences and future perspectives are reported in the present review. On-going and future clinical trials on sarcopenia may radically change our preventive and therapeutic approaches of mobility disability in older people.

Sex differences in lipolysis-regulating mechanisms in overweight subjects: effect of exercise intensity

OBJECTIVE

To explore sex differences in the regulation of lipolysis during exercise, the lipid-mobilizing mechanisms in the subcutaneous adipose tissue (SCAT) of overweight men and women were studied using microdialysis.

RESEARCH METHODS AND PROCEDURES

Subjects matched for age, BMI, and physical fitness performed two 30-minute exercise bouts in a randomized fashion: the first test at 30% and 50% of their individual maximal oxygen uptake (Vo(2max)) and the second test at 30% and 70% of their Vo(2max).

RESULTS

In both groups, an exercise-dependent increment in extracellular glycerol concentration (EGC) was observed. Whatever the intensity, phentolamine [alpha-adrenergic receptor (AR) antagonist] added to a dialysis probe potentiated exercise-induced lipolysis only in men. In a probe containing phentolamine plus propranolol (beta-AR antagonist), no changes in EGC occurred when compared with the control probe when exercise was performed at 30% and 50% Vo(2max). A significant reduction of EGC (when compared with the control probe) was observed in women at 70% Vo(2max). At each exercise power, the plasma non-esterified fatty acid and glycerol concentrations were higher in women. Exercise-induced increase in plasma catecholamine levels was lower in women compared with men. Plasma insulin decreased and atrial natriuretic peptide increased similarly in both groups.

DISCUSSION

Overweight women mobilize more lipids (assessed by glycerol) than men during exercise. alpha(2)-Anti-lipolytic effect was functional in SCAT of men only. The major finding is that during low-to-moderate exercise periods (30% and 50% Vo(2max)), lipid mobilization in SCAT relies less on catecholamine-dependent stimulation of beta-ARs than on an increase in plasma atrial natriuretic peptide concentrations and the decrease in plasma insulin.

Lipid oxidation according to intensity and exercise duration in overweight men and women

OBJECTIVE

Our objective was to compare the effect of different exercise intensities on lipid oxidation in overweight men and women.

RESEARCH METHODS AND PROCEDURES

Nine young, healthy, overweight men and women were studied (age, 31.4 +/- 2.3 and 26.7 +/- 2.1 years; BMI, 27.9 +/- 0.4 and 27.2 +/- 0.5; for men and women, respectively). On one study day, the subjects first performed 30 minutes of cycling exercise at 30% of their maximal oxygen uptake (Vo(2max); E1 session), followed by 30 minutes of exercise at 50% Vo(2max) (E2 session). On a second study day, a similar E1 session was followed by 30 minutes of exercise at 70% Vo(2max) (E3 session). From the gas exchange measurements, the respiratory exchange ratio (RER) and the fat oxidation rate (FOR) were calculated. Plasma concentrations of glycerol and non-esterified fatty acids (NEFAs) were assayed.

RESULTS

RER was significantly lower for women during only the E1 session. For both sexes, RER decreased over time during the E2 and E3 sessions. During the E1 session, the FOR per kilogram of lean mass (LM) was higher among women, and it did not change over time despite an increase in plasma NEFAs. FOR per kilogram of LM was higher during the E2 exercise for both sexes. During E2 and E3 sessions, as the exercise time was prolonged, the FOR/kg LM increased simultaneously with the increase in the plasma glycerol.

DISCUSSION

Lipid oxidation during exercise is optimized for moderate and lengthy exercise. The enhancement of lipid oxidation occurring over time during moderate- and high-intensity exercises could be, in part, linked to the improvement of lipid mobilization. This fact is discussed to shed light on exercise modalities as a tool for the management of overweight.

Atrial natriuretic peptide contribution to lipid mobilization and utilization during head-down bed rest in humans

Head-down bed rest (HDBR) increases plasma levels of atrial natriuretic peptide (ANP) and decreases norepinephrine levels. We previously demonstrated that ANP promotes lipid mobilization and utilization, an effect independent of sympathetic nervous system activation, when infused into lean healthy men at pharmacological doses. The purpose of the present study was to demonstrate that a physiological increase in ANP contributes to lipid mobilization and oxidation in healthy young men. Eight men were positioned for 4 h in a sitting (control) or in a HDBR position. Indexes of lipid mobilization and hormonal changes were measured in plasma. Extracellular glycerol, an index of lipolysis, was determined in subcutaneous adipose tissue (SCAT) with a microdialysis technique. A twofold increase in plasma ANP concentration was observed after 60 min of HDBR, and a plateau was maintained thereafter. Plasma norepinephrine decreased by 30-40% during HDBR, while plasma insulin and glucose levels did not change. The level of plasma nonesterified fatty acids was higher during HDBR. SCAT lipolysis, as reflected by interstitial glycerol, as well as interstitial cGMP, the second messenger of the ANP pathway, increased during HDBR. This was associated with an increase in blood flow observed throughout HDBR. Significant changes in respiratory exchange ratio and percent use of lipid and carbohydrate were seen only after 3 h of HDBR. Thus the proportion of lipid oxidized increased by 40% after 3 h of HDBR. The rise in plasma ANP during HDBR was associated with increased lipolysis in SCAT and whole body lipid oxidation. In this physiological setting, independent of increasing catecholamines, our study suggests that ANP contributes to lipid mobilization and oxidation in healthy young men.

Exercise program for nursing home residents with Alzheimer's disease: a 1-year randomized, controlled trial

OBJECTIVES

To investigate the effectiveness of an exercise program in improving ability to perform activities of daily living (ADLs), physical performance, and nutritional status and decreasing behavioral disturbance and depression in patients with Alzheimer's disease (AD).

DESIGN

Randomized, controlled trial.

SETTING

Five nursing homes.

PARTICIPANTS

One hundred thirty-four ambulatory patients with mild to severe AD.

INTERVENTION

Collective exercise program (1 hour, twice weekly of walk, strength, balance, and flexibility training) or routine medical care for 12 months.

MEASUREMENTS

ADLs were assessed using the Katz Index of ADLs. Physical performance was evaluated using 6-meter walking speed, the get-up-and-go test, and the one-leg-balance test. Behavioral disturbance, depression, and nutritional status were evaluated using the Neuropsychiatric Inventory, the Montgomery and Asberg Depression Rating Scale, and the Mini-Nutritional Assessment. For each outcome measure, the mean change from baseline to 12 months was calculated using intention-to-treat analysis.

RESULTS

ADL mean change from baseline score for exercise program patients showed a slower decline than in patients receiving routine medical care (12-month mean treatment differences: ADL=0.39, P=.02). A significant difference between the groups in favor of the exercise program was observed for 6-meter walking speed at 12 months. No effect was observed for behavioral disturbance, depression, or nutritional assessment scores. In the intervention group, adherence to the program sessions in exploratory analysis predicted change in ability to perform ADLs. No adverse effects of exercise occurred.

CONCLUSION

A simple exercise program, 1 hour twice a week, led to significantly slower decline in ADL score in patients with AD living in a nursing home than routine medical care.

Nutritional intake and recreational physical activity in healthy elderly women living in the community

PURPOSE

Recreational physical activity, which increases energy expenditure, may help to maintain proper food intake. To compare the nutritional intake of inactive, active and very active healthy elderly women.

METHODS

Eighty-two women were recruited in the community. Participants had to be > or = 65 years and in good health (< or = 2 drugs, < or = 1 major illness, < or = 1 surgical operation, no disability in basic or instrumental activities of daily living and no cognitive impairment). We compared food intakes between the 26 inactive (age 73.9 +/- 7.7 y, BMI 24.3 +/- 3.2 kg/m2), the 29 active (age 71.5 +/- 5.6 y, BMI 23.2 +/- 3.5 kg/m2) and the 27 very active (age 70.9 +/- 4.8 y, BMI 24.3 +/- 3.2 kg/m2) healthy women. The nutritional intake was evaluated by a three-day food record. Macronutrient, mineral and vitamin content were derived from tables. Self-reported type, duration and frequency of recreational physical activities during the last month were converted into energy expenditures.

RESULTS

Despite high levels of energy intake (mean 1743.9 kcal/d), mean intakes of calcium, vitamin B1, E and folic acid were lower than Recommended Dietary Allowances (-26.2%, -12%, -50.8%, -2.4% respectively) in the whole sample. There were no significant differences of energy intake and quantities of nutrients between the groups except for calcium intake which was significantly higher in inactive women (p=0.04).

CONCLUSION

Active healthy elderly women do not have a better nutritional profile than their inactive peers.

Training enhances ANP lipid-mobilizing action in adipose tissue of overweight men

PURPOSE

This study was designed to evaluate whether a 4-month endurance training program could improve ANP- as well as isoproterenol-mediated (beta-adrenergic receptor agonist) in situ lipolysis and adipose tissue blood flow (ATBF) in the subcutaneous adipose tissue (SCAT) of untrained overweight subjects.

METHODS

Ten overweight men aged 26.0 +/- 1.4 yr with a mean body mass index of 27.6 +/- 0.2 kg.m(-2), performed aerobic exercise 5 d.wk(-1) for 4 months. Before and after the training period, SCAT responsiveness was investigated in situ during a 60-min infusion of 1 micromol.L(-1) isoproterenol and 10 micromol.L(-1) ANP through microdialysis probes. Plasma metabolic parameters and physical fitness variables were measured as well.

RESULTS

Endurance training significantly increased fat-free mass and VO2max, while reducing plasma insulin, glucose, NEFA, low density lipoprotein (LDL)-C and the respiratory exchange ratio at rest. Training significantly lowered resting dialysate glycerol levels in SCAT. The lipid-mobilizing effect of ANP was markedly enhanced (by 191%, P < 0.05) after training as was that of isoproterenol (by 145%, P < 0.05). Resting adipose tissue blood flow as well as ANP- and isoproterenol-mediated rise in ATBF was increased after training.

CONCLUSION

The present study shows that endurance training improves ANP- as well as beta-adrenergic-receptor-mediated lipid mobilization and ATBF in the SCAT of overweight subjects. The recovery of a higher lipolytic efficiency in adipose tissue is an important benefit of a training program in overweight subjects.

Stroke output variations calculated by esophageal Doppler is a reliable predictor of fluid response

OBJECTIVE

Esophageal Doppler allows continuous monitoring of stroke volume index (SVI) and corrected flow time (FTc). We hypothesized that variations in stroke output index SOI (SVI/FTc) during volume expansion can predict the hemodynamic response to subsequent fluid loading better than the static values.

DESIGN AND SETTING

Prospective study in the intensive care unit of a university hospital.

PATIENTS

Fifty-one patients with circulatory failure were monitored by esophageal Doppler.

INTERVENTIONS

Patients who responded to a first fluid challenge received a second one. Patients who responded to both were classified as responders-responders, and those who did not respond to the second as responders-nonresponders. In these two groups we compared DeltaSVI, DeltaFTc, and DeltaSOI during each fluid challenge and also static values at the end of each fluid challenge.

MEASUREMENTS AND RESULTS

After the first fluid challenge DeltaSOI and DeltaSVI were significantly higher in patients who responded to subsequent volume expansion than in patients who no longer responded. ROC curves showed that DeltaSOI was a better predictor of fluid responsiveness than DeltaSVI. During volume expansion a DeltaSOI value of 11% discriminated between responders and nonresponders to subsequent volume expansion with a sensitivity of 91% and a specificity of 97%. There was no significant difference between the two groups for FTc value at the end of first fluid challenge.

CONCLUSIONS

Analysis of DeltaSOI during fluid challenge predicts response to subsequent fluid challenge and FTc is not a reliable indicator of cardiac preload.

Rehabilitation outcome of elderly patients with hip fracture and cognitive impairment

PURPOSE

To assess the association between cognitive status and functional gain during a rehabilitation programme for elderly patients with hip fracture.

METHOD

Prospective study in a hospital geriatric rehabilitation unit. Sixty-one consecutive patients were studied: 28 with cognitive impairment (age 87.6 +/- 7.2 years, Mini Mental State Examination (MMSE) score 11.25 +/- 5.9), 23 with possible cognitive impairment (age 83.9 +/- 6.8 years, MMSE 22.65 +/- 1.6) and 10 without cognitive impairment (age 77.6 +/- 7.4 years, MMSE 29.5 +/- 0.9). Cognitive status was assessed with the MMSE and admission and discharge functional status with the Functional Independence Measure (FIM). Functional gain was calculated by absolute FIM gain (admission FIM minus discharge FIM), relative (to maximum potential) FIM gain with the Montebello Rehabilitation Factor Score (MRFS) and analysis of covariance of the FIM (ANCOVA).

RESULTS

Patients without cognitive impairment had significantly higher admission FIM and discharge FIM. Cognitive status was not significantly associated with absolute functional gain. The adjusted (age, gender, sensory impairment, nutritional status, comorbidity and treatment) MRFS score of cognitively impaired patients was significantly lower (p < 0.03). However, the functional gain related to baseline functional status (ANCOVA) was not significantly different between the groups.

CONCLUSIONS

In spite of cognitive impairment, elderly patients with hip fracture can benefit from participation in rehabilitation programmes.

Aerobic training improves exercise-induced lipolysis in SCAT and lipid utilization in overweight men

The aim of this study was to investigate whether endurance training improves lipid mobilization and oxidation in overweight subjects. Eleven young men (25.6 +/- 1.4 yr and body mass index 27.7 +/- 0.2) performed a 4-mo training program consisting of practicing aerobic exercise 5 days/wk. Before and after the training period, lipid oxidation was explored during a 60-min exercise at 50% of peak O2 consumption by use of indirect calorimetry. Lipid mobilization and antilipolytic alpha2-adrenoceptor effect were also studied using the microdialysis method in abdominal subcutaneous adipose tissue (SCAT). After training, plasma nonesterified fatty acid (NEFA) levels, at rest and during exercise, were significantly lower than before (P < 0.001). Lipolysis in SCAT was significantly higher after than before training. An antilipolytic alpha2-adrenoceptor effect in SCAT was underlined during exercise before training and disappeared after. The respiratory exchange ratio was lower after training, i.e., the percentage of lipid oxidation was higher only at rest. The amount of lipid oxidized was higher after training, at rest, and during exercise. Although exercise power was higher after training, the relative intensity was equivalent, as suggested by a similar increase in plasma catecholamine concentrations before and after training. In conclusion, 4-mo training in overweight men improved lipid mobilization through a decrease of antilipolytic alpha2-adrenoceptor effect in SCAT and lipid oxidation during moderate exercise. Training induced a decrease of blood NEFA, predicting better prevention of obesity.

Strenuous but not moderate exercise increases the thrombotic tendency in healthy sedentary male volunteers

We have investigated the effect of moderate and strenuous exercise on experimental arterial thrombus formation in men. Thrombogenesis was measured in 15 sedentary healthy male volunteers at rest or immediately after two standardized exercise tests performed for 30 min on a bicycle ergometer. The exercises were performed at a constant load corresponding to either 50 or 70% maximal oxygen uptake. Thrombus formation was induced ex vivo by exposing a collagen-coated coverslip in a parallel plate perfusion chamber to native nonanticoagulated blood for 3 min. The shear rate at the collagen surface was 2,600 s(-1). Platelet and fibrin deposition was quantified by immunoenzymatic methods. The results show that moderate exercise did not affect arterial thrombus formation. In contrast, platelet thrombus formation on collagen was increased on the average by 20% after 30 min at 70% maximal oxygen uptake (P = 0.03). Fibrin deposition on collagen remained unchanged with exercise, regardless of its intensity. Thus, with the use of a clinically relevant human experimental model of thrombosis, the present study suggests that exercise of heavy intensity may increase the risk for arterial thrombogenesis in sedentary young healthy male volunteers.

[Sport practice and cannabis consumption in a representative sample of French high school adolescents]

PURPOSE

- To assess the association between cannabis consumption and sport practice.

METHODS

We randomised a representative sample of 1,506 girls and 1,420 boys from the third to the last year of school in the French Midi-Pyrénées region, excluding classes reserved for children practising high level sport. Information was collected by self-answer questionnaire.

RESULTS

More than 90% of boys and 70% of girls declared they practised sport outside physical education at school (athletic students). Among boys, sport practice mainly concerned activities in clubs or competitions (respectively 66% and 60%, against 35% and 27% among girls; p<0.001). Twenty-eight percents of boys and 19% of girls declared they had consumed cannabis (at least occasionnally, during or outside sport). Among athletic students, such potential consumption concerned 28.6% of boys and 19.6% of girls (p<0.001). Moreover, 1.2% of athletic students (n=7) declared they had already consumed cannabis during the practice sport with clubs or competitions. Among boys, this potential consumption increased with age, was lower among non-athletic students and the most athletic students, but was highest among those practising an individual "X-treme" sport (50% in this group versus 26% among athletes practising collective or non- "X-treme" sport; p<0.001). Potential cannabis consumption was also highest among athletes who declared they practiced sport for seeking emotions, who did not practise sport for health benefits but who considered that sport could involve taking risks.

CONCLUSION

It seems more important to consider how sport is practised rather than its intensity when assessing the association between sport and cannabis consumption. Indeed, sport appears to be more favourable for cannabis consumption when associated with ideas of emotion and risk and when practised outside of an organisation.

Feasibility [corrected] of regular physical exercise for patients with moderate to severe Alzheimer disease

BACKGROUND

Physical activity delays loss of autonomy in the elderly. In patients with Alzheimer disease (AD), physical activity could be a useful strategy in therapeutic management by delaying loss of functional independence and the usual complications of the disease.

OBJECTIVE

To determine, using standardized tools, the effects on autonomy (ADL, IADL), cognitive function (MMS), nutritional status (MNA), behavioral problems (NPI) and risk of falls (Tinetti test) of a physical exercise program in patients with AD.

DESIGN

Twenty-three subjects (13 men and 10 women, aged 71-92 years, mean 78 years) with AD (mean MMS 16, range 1-23) carried out for a mean of 7 weeks (5-12 weeks) a program of endurance exercise (walking, exercise bicycle) adapted to their individual capacities. Standardized gerontological evaluation was performed before and after the study.

RESULTS

No significant change in autonomy (ADL, IADL) was observed. There was an improvement in the MNA (p<0.001) and the MMS (p<0.001). Risk of falls (p<0.01) and behavioral problems (p<0.05) decreased. These results were obtained without increasing family workload.

CONCLUSION

We suggest that physical activity is a therapeutic option which can reduce nutritional and behavioral complications and risk of falls in subjects with AD.

[Asthma drugs and doping]

Some drugs regularly used in the treatment of asthma (beta-agonists and corticosteroids) are registered on the list of drugs forbidden in sport, because they have a doping action. To avoid penalizing asthmatic sportsmen, some beta-agonists (Salbutamol, Salmeterol, Terbutaline) and corticosteroids are allowed only in inhaled form, with written notification from the prescribing physician, a pneumologist or the team doctor. Considering the increase of doping with increasing involvement of physicians, good and up to date notions about the current rules of prescription in asthmatic sportsmen are needed.