Fetal Heart Race and Maternal Cardiovascular and Catecholamine Responses to Dynamic Exercise

Abstract

Fourteen women performed treadmill exercise for continuous 10-minute periods at levels of 2, 3 and 4 mets in the second and third trimester of pregnancy and again postpartum. The percentage increase in heart rate in response to exercise was similar during pregnancy and postpartum while systolic blood pressure was increased only during pregnancy. Maternal plasma noradrenaline levels at peak exercise increased 64% (p less than 0.005), 42% (p less than 0.005) and 29% (NS) in the 3 studies respectively compared to resting levels at these times. Ten women experienced increased uterine activity during the exercise or recovery periods. Fetal heart rate was increased (p less than 0.05) by exercise but this was independent of uterine contractions and plasma noradrenaline levels.

Comparação do índice de esforço percebido e consumo de oxigênio em exercício em cicloergômetro entre gestantes e não-gestantes e entre o exercício aquático e terrestre

“…However, this statement is questioned by some authors who state that during pregnancy many physiological variables are altered and this fact may alter their perceived exertion to exercise [7][8][9] . In the literature, there are studies which measure the role of the RPE in the prescription of different exercise modalities [10][11][12][13][14] and have been also used in investigations which need to prescribe the exercise intensity in different environment [15][16][17] .…”

“…Another important aspect is related to the different types of exercise assessed in the mentioned studies. The physiological responses are different if an exercise in which the individual does not need to sustain body weight, such as exercise in cycle ergometer used in the present study, and an exercise which body weight needs to be sustained, as exercise on treadmill are compared 8 . Concerning this issue, Pivarnik et al 11 compared the exercise RPE in cycle ergometer and treadmill.…”

“…This control was performed with the aim to avoid interference in the collected variables. Moreover, the participants were familiarized with the Borg's scale (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20).…”

Physiology of Prenatal Exercise and Fetal Development

“…From Jovanovic et al (1985) the decreased fetal HR was during exercise, but increased after exercise. Regardless of whether a woman is conditioned or not prior to conception, the majority of studies found that an acute bout of maternal aerobic exercise elicits an increased FHR response (Hauth et al 1982;Collings et al 1983;Clapp 1985;Collings and Curet 1985;Cooper et al 1987;Steegers et al 1988;van Doorn et al 1992;Clapp et al 1993;Webb et al 1994;McMurray et al 1995;O'Neill 1996;Manders et al 1997;Brenner et al 1999;MacPhail et al 2000;Kennelly et al 2002b).…”

“…For adults, this response is related to the level of circulating catecholamines which stimulate the heart and lead to increased HR and lower HRV. Interestingly, maternal catecholamines also increased with maternal exercise level and catecholamines are measured in the amniotic fluid (Cooper et al 1987).…”