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V L Foster

Publications and source records attributed to V L Foster.

4 recordsLinked to original sources

Endurance training for elderly women: moderate vs low intensity.

This investigation evaluated the efficacy of training at moderate-60% Maximal Heart Rate Reserve, HRRmax, (MOD) and low-40% HRRmax (LOW) intensities in a population of older American women (N = 16, mean age = 78.4 years). Prior to and immediately following a 10-week training program consisting of exercising at the prescribed heart-rate intensity with a caloric expenditure of 100 calories, the following measurements were performed: Maximal oxygen consumption (VO2max), Maximal Lactate Production (HLAmax), Maximal Heart Rate (HRmax), Maximal Workstage (WSmax), Total Cholesterol (TOTC), High Density Lipoprotein Cholesterol (HDLC), and Rate Pressure Product Max (RPPmax). Significant differences, p less than .05, were noted pre- to post-training for measures of VO2max, whether expressed in 1.min-1 or ml.kg-1.min-1, and WSmax. No statistical differences existed between the groups pre- or post-training for these measures. The results suggest that the low-intensity exercise prescription provides an adequate training stimulus for older women who have been sedentary and who might be at higher risk for cardiac or musculoskeletal injury, particularly at the initiation of an exercise program.

Aged

Effect of training/detraining on submaximal exercise responses in humans.

Human subjects participated in a training/detraining paradigm which consisted of 7 wk of intense endurance training followed by 3 wk of inactivity. In previously sedentary subjects, training produced a 23.9 +/- 7.2% increase in maximal aerobic power (V02max) (group S). Detraining did not affect group S V02max. In previously trained subjects (group T), the training/detraining paradigm did not affect V02max. In group S, training produced an increase in vastus lateralis muscle citrate synthase (CS) activities (nmol.mg protein-1. min-1) from 67.1 +/- 14.5 to 106.9 +/- 22.0. Detraining produced a decrease in CS activity to 80 +/- 14.6. In group T, pretraining CS activity (139.5 +/- 14.9) did not change in response to training. Detraining, however, produced a decrease in CS activity (121.5 +/- 7.8 to 66.8 +/- 5.9). Group S respiratory exchange ratios obtained during submaximal exercise at 60% V02max (R60) decreased in response to training (1.00 +/- 0.02 to 0.87 +/- 0.02) and increased (0.96 +/- 0.02) after detraining. Group T R60 (0.91 +/- 0.01) was not affected by training but increased (0.89 +/- 0.02 to 0.95 +/- 0.02) after detraining. R60 was correlated to changes in CS activity but was unrelated to changes in V02max. These data support the hypothesis that the mitochondrial content of working skeletal muscle is an important determinant of substrate utilization during submaximal exercise.

Adult

The reproducibility of VO2max, ventilatory, and lactate thresholds in elderly women.

The reproducibility of VO2max, ventilatory, and lactate thresholds in elderly women. Med. Sci. Sports Exerc., Vol. 18, No. 4, pp. 425-430, 1986. This investigation examined the reproducibility of maximal (VO2max) and submaximal measures of fitness for elderly women. Eight subjects [age (yr): mean = 80.6 +/- 3.7; range = 73-86] volunteered to repeat three continuous, incremental maximal effort treadmill tests. Blood lactate determinations were made for each increment from blood samples taken from an indwelling venous catheter located in the back of the hand. Average VO2max values (ml X min-1 X kg X l-1) were 13.21 + 1.95 for test 1, 13.44 +/- 1.83 for test 2, and 13.62 + 2.95 for test 3. In all but one subject, a threshold was not definable by either ventilatory or lactate measurements. Maximal lactate values were low, with the average values for tests 1, 2, and 3 being 1.89, 1.46, and 1.86 mmol X l-1, respectively. The data demonstrates that VO2max is reproducible for older women and can, therefore, be used for fitness assessment and exercise prescription. The use of ventilatory or lactate thresholds as submaximal measures of fitness or as minimal intensities for exercise prescription was determined not to be applicable for women in the eighth and ninth decades of life.

Aged