Cardiovascular fitness, body composition, and lipoprotein lipid metabolism in older men.

Background: Lipoprotein lipids in older individuals are affected by family history of coronary artery disease (CAD), obesity, diet, and physical activity habits.

Methods: The relationship of obesity and physical fitness (VO2max) to lipoprotein lipids and postheparin lipases was examined in a cross-sectional study of 12 lean (LS) and 26 obese (OS) sedentary men and 18 master athletes (MAs) aged 65+/-1 years (mean +/- SE). The men were healthy, had no family history of CAD, and were weight stable on AHA diets at the time of study.

Interrelationships of spontaneous growth hormone axis activity, body fat, and serum lipids in healthy elderly women and men.

Aging is associated with decreased growth hormone (GH) secretion and plasma insulin-like growth factor-I (IGF-I) levels, increased total and abdominal fat, total and low-density lipoprotein (LDL) cholesterol, and triglycerides, and reduced high-density lipoprotein (HDL) cholesterol. Similar changes in lipids and body composition occur in nonelderly GH-deficient adults and are reversed with GH administration. To examine whether GH/IGF-I axis function in the elderly is related to the lipid profile independently of body fat, we evaluated GH secretion, serum IGF-I and IGF binding protein-3 (IGFBP-3) levels, adiposity via the body mass index (BMI), waist to hip ratio (WHR), dual-energy x-ray absorptiometry (DEXA), and magnetic resonance imaging (MRI), and circulating lipids in 101 healthy subjects older than 65 years.

Predictors of adipose tissue lipoprotein lipase in middle-aged and older men: relationship to leptin and obesity, but not cardiovascular fitness.

The effects of long-term endurance exercise training, body composition, and cardiovascular fitness (VO2max) on the activity of adipose tissue lipoprotein lipase (AT-LPL) and lipoprotein lipids were examined in 66 healthy age-matched middle-aged and older men (mean +/- SE, 61 +/- 1 years). We compared subcutaneous abdominal (ABD) and gluteal (GLT) heparin-elutable AT-LPL activity in 19 master athletes (VO2max > 40 mL/kg/min) and 20 lean sedentary men (VO2max < 40 mL/kg/min) versus 27 obese sedentary men (VO2max < 40 mL/kg/min; body fat > 27%). Fasting insulin and leptin levels were similar in master athletes and lean sedentary men, but were lower than in obese sedentary men.

Energy requirements of middle-aged men are modifiable by physical activity.

Background: Energy requirements for weight maintenance decrease with age. Often, this decline is not proportionately matched by reduced energy intake, resulting in weight gain.

Objective: We hypothesized that energy requirements for total daily weight maintenance in healthy, sedentary, middle-aged men would increase after regular aerobic exercise or aerobic exercise plus weight loss to levels comparable with those in middle-aged athletes.

Exercise-induced silent myocardial ischemia in master athletes.

High-physical activity levels are associated with reduced risk of symptomatic coronary artery disease (CAD). However, there are a number of reports of exercise-related sudden death and myocardial infarction in aerobically trained athletes. This study compared the prevalence of exercise-induced silent myocardial ischemia on maximum graded exercise tests with tomographic thallium scintigraphy in 70 master male athletes (63 +/- 6 years, mean +/- SD) (maximum aerobic capacity, VO2max >40 ml/kg/min) and in 85 healthy untrained men (61 +/- 7 years) with no history of CAD.