The Evolution of Skeletal Muscle Plasticity in Response to Physical Activity and Inactivity

Ovariectomized rodents model human menopause in that they rapidly gain weight, reduce spontaneous physical activity (SPA), and develop metabolic dysfunction, including insulin resistance. How contrasting aerobic fitness levels impacts ovariectomy (OVX)-associated metabolic dysfunction is not known. Female rats selectively bred for high and low intrinsic aerobic fitness [high-capacity runners (HCR) and low-capacity runners (LCR), respectively] were maintained under sedentary conditions for 39 wk. Midway through the observation period, OVX or sham (SHM) operations were performed providing HCR-SHM, HCR-OVX, LCR-SHM, and LCR-OVX groups. Glucose tolerance, energy expenditure, and SPA were measured before and 4 wk after surgery, while body composition via dual-energy X-ray absorptiometry and adipose tissue distribution, brown adipose tissue (BAT), and skeletal muscle phenotype, hepatic lipid content, insulin resistance via homeostatic assessment model of insulin resistance and AdipoIR, and blood lipids were assessed at death. Remarkably, HCR were protected from OVX-associated increases in adiposity and insulin resistance, observed only in LCR. HCR rats were ∼30% smaller, had ∼70% greater spontaneous physical activity (SPA), consumed ∼10% more relative energy, had greater skeletal muscle proliferator-activated receptor coactivator 1-alpha, and ∼40% more BAT. OVX did not increase energy intake and reduced SPA to the same extent in both HCR and LCR. LCR were particularly affected by an OVX-associated reduction in resting energy expenditure and experienced a reduction in relative BAT; resting energy expenditure correlated positively with BAT across all animals ( r = 0.6; P < 0.001). In conclusion, despite reduced SPA following OVX, high intrinsic aerobic fitness protects against OVX-associated increases in adiposity and insulin resistance. The mechanism may involve preservation of resting energy expenditure.

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Physical activity and health, novel concepts and new targets: report from the 12th Conference of the International Research Group on the Biochemistry of Exercise

Proceedings of The Nutrition Society ◽

10.1079/pns2004353 ◽

2004 ◽

Vol 63 (2) ◽

pp. 189-197 ◽

Cited By ~ 3

Author(s):

Matthijs K. C. Hesselink ◽

Marleen A. van Baak

Keyword(s):

Physical Activity ◽

Skeletal Muscle ◽

Physical Exercise ◽

Health Effects ◽

Research Group ◽

International Research ◽

Biochemical Basis ◽

International Research Group ◽

Exercise Muscle ◽

Exercise Induced

The present paper is the introductory paper to a series of brief reviews representing the proceedings of a recent conference on ‘The biochemical basis for the health effects of exercise’ organized by the International Research Group on the Biochemistry of Exercise in conjunction with the Nutrition Society. Here the aim is to briefly review and highlight the main innovations presented during this meeting. The following topics were covered during the meeting: exercise signalling pathways controlling fuel oxidation during and after exercise; the fatty acid transporters of skeletal muscle; mechanisms involved in exercise-induced mitochondrial biogenesis in skeletal muscle; new methodologies and insights in the regulation of fat metabolism during exercise; muscle hypertrophy: the signals of insulin, amino acids and exercise; adipose tissue–liver–muscle interactions leading to insulin resistance. In these symposia state-of-the-art knowledge on how physical exercise exerts its effects on health was presented. The fast-growing number of identified pathways and processes involved in the health effects of physical exercise, which were discussed during the meeting, will help to develop tailored physical-activity regimens in the prevention of inactivity-induced deterioration of health.

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AN INFLUENCE OF PHYSICAL ACTIVITY AND CARBOHYDRATE RATION ON SUPEROXIDE DISMUTASE (SOD) ACTIVITY AND DIENE CONCENTRATIONS IN BLOOD AND SKELETAL MUSCLE OF RATS

Shock ◽

10.1097/00024382-199512001-00222 ◽

1995 ◽

Vol 4 (Supplement) ◽

pp. 55

Author(s):

V. I. Morozov ◽

S. A. Logosha ◽

V. A. Rogozkin

Keyword(s):

Physical Activity ◽

Skeletal Muscle ◽

Superoxide Dismutase ◽

Sod Activity

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THU0358 NEGATIVE CHANGES OF BODY COMPOSITION IN MYOSITIS PATIENTS AND THEIR ASSOCIATION WITH DISEASE SPECIFIC CHARACTERISTICS, PHYSICAL ACTIVITY AND NUTRITIONAL STATUS.

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.6050 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 410.3-410

Author(s):

S. Oreska ◽

M. Špiritović ◽

P. Česák ◽

O. Marecek ◽

H. Štorkánová ◽

...

Keyword(s):

Physical Activity ◽

Skeletal Muscle ◽

Body Composition ◽

Lipid Metabolism ◽

Nutritional Status ◽

Disease Activity ◽

Inflammatory Cytokines ◽

Disease Duration ◽

Serum Levels ◽

Muscle Involvement

Background:Skeletal muscle, pulmonary and articular involvement in idiopathic inflammatory myopathies (IIM) limit the mobility/self-sufficiency of patients, and can have a negative impact on body composition.Objectives:The aim was to assess body composition and physical activity of IIM patients and healthy controls (HC) and the association with selected inflammatory cytokines/chemokines and laboratory markers of nutrition and lipid metabolism.Methods:54 patients with IIM (45 females; mean age 57.7; disease duration 5.8 years; polymyositis (PM, 22) / dermatomyositis (DM, 25) / necrotizing myopathy (IMNM, 7)) and 54 age-/sex-matched HC (45 females, mean age 57.7) without rheumatic/tumor diseases were included. PM/DM patients fulfilled Bohan/Peter criteria for PM/DM. We assessed body composition (densitometry: iDXA Lunar, bioelectric impedance: BIA2000-M), physical activity (Human Activity Profile, HAP questionnaire), serum levels of 27 cytokines/chemokines (commercial multiplex ELISA kit, Bio-Rad Laboratories) and serum levels of selected parameters of nutrition and lipidogram. Disease activity (MITAX and MYOACT activity score) and muscle involvement (manual muscle testing, MMT-8, and functional index 2, FI2) were evaluated. Data are presented as mean±SD.Results:Compared to HC, patients with IIM had a trend towards significantly increased body fat % (BF%; iDXA: 39.9±7.1 vs. 42.4±7.1 %, p=0.077), but significantly decreased lean body mass (LBM; iDXA: 45.6±8.1 vs. 40.6±7.2 kg, p=0.001; BIA: 52.6±8.8 vs. 48.7±9.0 kg, p=0.023), increased extracellular mass/body cell mass (ECM/BCM) ratio (1.06±0.15 vs. 1.44±0.42, p<0.001), reflecting deteriorated nutritional status and predisposition for physical activity, and significantly lower bone mineral density (BMD: 1.2±0.1 vs. 1.1±0.1 g/cm2, p<0.001). Disease duration negatively correlated with BMD and LBM-BIA. Disease activity (MITAX, MYOACT) positively correlated with LBM (by BIA and DXA), similarly as with basal metabolic rate (BMR), and fat free mass (FFM). CRP was positively associated with BF% (BIA and DXA). Higher BF%-DEXA was associated with worse physical endurance (FI2) and worse ability to perform physical activity (HAP). MMT-8 score negatively correlated with ECM/BCM ratio. Serum levels of several inflammatory cytokines/chemokines (specifically IL-1ra, MCP, IL-10) and markers of nutrition (specifically albumin, C3-, C4-complement, cholinesterase, amylase, insulin and C-peptide, vitamin-D, orosomucoid), and lipid metabolism (specifically triglycerides, high-density lipoprotein, apolipoprotein A and B, atherogenic index of plasma) were significantly associated with alterations of body composition in IIM patients. (p<0.05 for all correlations)Conclusion:Compared to healthy age-/sex-matched individuals we found significant negative changes in body composition of our IIM patients associated with their disease activity and duration, inflammatory status, skeletal muscle involvement, and physical activity. These data could reflect their impaired nutritional status and predispositions for physical exercise, aerobic fitness and performance.Serum levels of certain inflammatory cytokines/chemokines and markers of nutrition and lipid metabolism were associated with alterations of body composition in IIM patients. This might further support the role of systemic inflammation and nutritional status on the negative changes in body composition of IIM patients.Acknowledgments:Supported by AZV NV18-01-00161A, MHCR 023728, SVV 260373 and GAUK 312218Disclosure of Interests:Sabina Oreska: None declared, Maja Špiritović: None declared, Petr Česák: None declared, Ondrej Marecek: None declared, Hana Štorkánová: None declared, Barbora Heřmánková: None declared, Kateřina Kubinova: None declared, Martin Klein: None declared, Lucia Vernerová: None declared, Olga Růžičková: None declared, Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Ladislav Šenolt: None declared, Heřman Mann: None declared, Jiří Vencovský: None declared, Michal Tomčík: None declared

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Interactions between insulin and exercise

Biochemical Journal ◽

10.1042/bcj20210185 ◽

2021 ◽

Vol 478 (21) ◽

pp. 3827-3846

Author(s):

Erik A. Richter ◽

Lykke Sylow ◽

Mark Hargreaves

Keyword(s):

Physical Activity ◽

Skeletal Muscle ◽

Adipose Tissue ◽

Insulin Sensitivity ◽

Insulin Action ◽

Regular Exercise ◽

Fuel Storage ◽

Storage Effects ◽

Glucose Storage ◽

Glycogen Stores

The interaction between insulin and exercise is an example of balancing and modifying the effects of two opposing metabolic regulatory forces under varying conditions. While insulin is secreted after food intake and is the primary hormone increasing glucose storage as glycogen and fatty acid storage as triglycerides, exercise is a condition where fuel stores need to be mobilized and oxidized. Thus, during physical activity the fuel storage effects of insulin need to be suppressed. This is done primarily by inhibiting insulin secretion during exercise as well as activating local and systemic fuel mobilizing processes. In contrast, following exercise there is a need for refilling the fuel depots mobilized during exercise, particularly the glycogen stores in muscle. This process is facilitated by an increase in insulin sensitivity of the muscles previously engaged in physical activity which directs glucose to glycogen resynthesis. In physically trained individuals, insulin sensitivity is also higher than in untrained individuals due to adaptations in the vasculature, skeletal muscle and adipose tissue. In this paper, we review the interactions between insulin and exercise during and after exercise, as well as the effects of regular exercise training on insulin action.

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