Change in muscle strength of the hand flexors, muscle-to-fat ratio and walking speed in ­middle-aged patients living in rural areas after myocardial infarction during cardiac rehabilitation

Aim. To estimate in dynamics the changes in muscle strength of hand flexors, muscle mass and gait rate in men with ischemic heart disease and myocardial infarction during cardiac rehabilitation at the outpatient polyclinic stage where daily dosed walking with individually selected frequency steps under self-control was used as a phy­sical component.

Methods. The study included 66 men. Patients were divided into two groups comparable by age: 41 men with myocardial infarction (mean age 56.49±7.33 years) and 25 men with exertional angina without myocardial infarction (mean age 61.09±4.67 years). In all patients before and after 3 months of cardiac rehabilitation, where the physical component was represented by dosed walking, clinical and anamnestic characteristics were determined, muscle mass using bioimpedancemetry, muscle strength by wrist dynamometry, and walking speed using 6-minute walk test were measured. Statistical processing of the obtained materials was carried out by generally accepted methods.

Results. In patients with coronary heart disease and myocardial infarction, the muscle strength of the hand flexor on the right hand increased from 45.26±11 daN to 46.3±7 daN (p=0.05) and on the left hand from 43.78±11 to 43.78±11 (p=0.05), absence of changes in muscle-to-fat tissue ratio 48.5 (47.7; 49.7) to 48.9 (48.5; 49.9) (p=0.08), increase in gait speed from 450 m (420; 500) to 480 m (440; 500) (p=0.05). In patients with coronary heart disease without myocardial infarction, muscle-to-fat tissue ratio decreased from 48.6 (47.7; 49.2) to 47.7 (46.5; 48.3) (p=0.04); gait speed decreased from 400 m (380; 431) to 390 m (350; 400) (p=0.05), the muscle strength of the hand flexors did not change (from 45.72±8.03 to 44.8±8 for the right hand (p=0.54) and from 42.18±10 to 42.6±10 for the left hand (p=0.6).

Conclusion. After 3 months of cardiac rehabilitation at the outpatient polyclinic stage, patients with myocardial infarction had a positive effect reflected by muscle strength of flexors on both hands, insignificant increase of muscle mass relative to fat tissue and increase of gait speed as opposed to patients with coronary heart disease without myocardial infarction, who had a decrease in muscle strength of hand flexors, muscle-to-fat tissue ratio and gait speed during this period of time.