The effect of physical activity on breast cancer risk: a cohort study of 30,548 women.

Background: In epidemiological studies abundant physical activity has been related to decreased breast cancer risk, though the results have been inconsistent. The purpose of this paper was to study the association of physical activity at leisure and commuting to work and incidence of breast cancer.

Methods: The study cohort consisted of 30,548 female participants of the Finnish adult health behaviour survey, based on annual random samples of Finns aged 15-64, collected in 1978-1993.

Relationship between the risk of breast cancer and physical activity. An epidemiological perspective.

The possible protective effect of physical exercise on the risk of breast cancer has gained attention during the last few years. According to the current concepts of biological mechanisms underlying the possible protection, physical activity may alter menstrual function by reducing the number of ovulatory menstrual cycles via a hormone-related pathway and, thus, reducing the cumulative exposure to progesterone and estrogen. Experimental studies on the effects of exercise suggest changes in menstrual characteristics and in ovarian hormone serum levels.

The association of trunk muscle cross-sectional area and magnetic resonance image parameters with isokinetic and psychophysical lifting strength and static back muscle endurance in men.

The relationship between trunk muscle morphology as measured on transverse magnetic resonance images and isokinetic lifting, psychophysical lifting, and static back muscle endurance testing was examined in 110 men, ages 35-67 years (mean, 48 years), who had been chosen based on their exposure to a wide variety of occupational and leisure-time physical activities. The computed T2-relaxation times and the T2-weighted and proton density-weighted signal intensities of the erector spinae, quadratus lumborum, and psoas major muscles had almost no association with any of the strength tests. The cross-sectional areas of the muscles had good correlations with isokinetic lifting strength (r = 0.

Correlations of isokinetic and psychophysical back lift and static back extensor endurance tests in men.

Isokinetic lift, psychophysical lift, and static back endurance tests are among the most widely used measurements of muscle function for determining risk for, and recovery from, back problems. After determining test repeatability we examined the degree of association between these test measures in 100 men selected to represent a variety of occupations and lifestyles. Isokinetic lifting had low correlations with test results for psychophysical lifting (r = 0.

Muscle and bone pressure pain threshold and pain tolerance in fibromyalgia patients and controls.

Pressure pain thresholds and pressure pain tolerances on non-trigger-point muscle and bone were measured with a dolorimeter in 46 female patients with primary fibromyalgia and in 50 healthy women of the same age. The pressure pain thresholds and the pressure pain tolerances on both muscle and bone were lower in the fibromyalgia patients than in the healthy controls. All the differences were statistically highly significant, though there was a certain degree of overlapping between the patients and the controls.