Showing papers by "Veronica K. Jamnik published in 1999"
TL;DR: Expansion of BV in elite ET cyclists, who already possess a high BV, does not improve their VO2max and endurance performance, and elite ET athletes may already be at an optimal BVs, which is at or near the limits of their diastolic reserve capacity.
Abstract: Induced hypervolemia, cardiac function, O2max, and performance of elite cyclists. Med. Sci. Sports Exerc., Vol. 31, No. 6, pp. 800-808, 1999.Objective:To determine whether plasma volume expansion (PVexp) in elite endurance-trained (ET) cyclists, who already possess both a high blood volume (
109 citations
TL;DR: Optimizing both [Hb] and BV is a very important consideration for endurance performance because a large portion of the difference in the enhanced cardiovascular function of endurance athletes is due to their high BV and the resultant enhancement of diastolic function.
Abstract: Alterations in [Hb], which are mediated through changes in arterial oxygen content, and alterations in BV, which are mediated through changes in cardiac output have a significant effect on both and...
89 citations
TL;DR: The decline in VO2max with age in ET women is due to decreases in maximal heart rate, stroke volume and cardiac output, and the primary advantage in the exercise cardiac performance of ET women of all ages is diastolic rather than systolic function.
Abstract: Purpose: To clarify the physiological reasons for the decline in aerobic power of endurance trained (ET) women with aging. Methods: Blood volume, JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max, and exercise cardiac function were examined in 23 ET women; six age 20-29 yr, six age 40-45 yr, six age 49-54 yr, and five age 58-63 yr. Results: Blood volume was unchanged with aging. JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max declined progressively at a rate of 0.51 mL·kg−1·min−1·yr−1. During maximal exercise, there was an increase in total peripheral resistance (TPR) and a decrease in heart rate, stroke volume, and cardiac output with increasing age. At all ages, cardiac filling (diastole) was significantly faster than cardiac emptying (systole). Stroke volume did not plateau at a submaximal work rate but increased progressively to maximum. Conclusions: The decline in JOURNAL/mespex/04.02/00005768-199905000-00016/ENTITY_OV0312/v/2017-07-20T222700Z/r/image-pngO2max with age in ET women is due to decreases in maximal heart rate, stroke volume and cardiac output, and the primary advantage in the exercise cardiac performance of ET women of all ages is diastolic rather than systolic function.
62 citations
1 citations