Substrate utilization and hormonal responses to moderate intensity exercise during pregnancy and after delivery


      Objective: This study was undertaken to examine substrate utilization and hormonal responses to moderate intensity exercise in the same group of women across gestation. Study design: Glucose, triglyceride, insulin, glucagon, cortisol, growth hormone, and blood urea nitrogen levels were measured in 12 women at rest and after exercise. Heart rate, oxygen uptake, and respiratory exchange ratio were measured at rest and during exercise. Urine urea nitrogen levels, urine volume, and creatinine levels were measured 24 hours before and after exercise. Each woman completed a 30-minute treadmill walk at 65% of her predicted maximal heart rate at the same time of day during the 22nd and 33rd weeks of gestation and at 14 weeks after delivery. Results: There were no significant differences between exercise trials in oxygen uptake, respiratory exchange ratio, or heart rate. Pregnancy elevated resting triglyceride levels but lowered plasma glucose levels. Exercise during pregnancy caused a reduction in plasma glucose levels but elevated circulating triglyceride levels (P < .05). Resting levels of cortisol, growth hormone, and insulin were elevated during pregnancy compared with after delivery, but resting glucagon levels were not affected by pregnancy. Exercise caused circulating levels of cortisol, growth hormone, and glucagon to increase (P < .05). The exercise-induced change in the cortisol level was greater during pregnancy than that after delivery. The exercise-induced changes in growth hormone and glucagon levels were greatest after delivery compared with those during pregnancy (P < .05). Exercise reduced insulin levels (P < .05), with the greatest reduction at 33 weeks' gestation. There were no significant differences in urine urea nitrogen excretion as a result of exercise. Conclusions: Certain substrate and hormonal responses to exercise are altered as pregnancy progresses. Quantitatively, protein appears to be a relatively unimportant fuel during a 30-minute bout of moderate intensity exercise in this group of women evaluated during pregnancy and after delivery. Furthermore, a 30-minute bout of moderate intensity exercise would not be expected to compromise fetal amino acid availability. (Am J Obstet Gynecol 2002;186:757-64.)


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Obstetrics & Gynecology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Bonen A
        • Campagna P
        • Gilchrist L
        • Young DC
        • Beresford P
        Substrate and endocrine responses during exercise at selected stages of pregnancy.
        J Appl Physiol. 1992; 73: 134-142
        • Clapp JF
        • Wesley M
        • Sleamaker RH
        Thermoregulatory and metabolic responses to jogging prior to and during pregnancy.
        Med Sci Sports Exerc. 1987; 19: 124-130
        • McMurray RG
        • Hackney AC
        • Guion WK
        • Katz VL
        Metabolic and hormonal responses to low impact aerobic dance during pregnancy.
        Med Sci Sports Exerc. 1996; 28: 41-46
        • McMurray RG
        • Katz VL
        • Berry MJ
        • Cefalo RC
        The effect of pregnancy on metabolic responses during rest, immersion, and aerobic exercise in the water.
        Am J Obstet Gynecol. 1988; 158: 481-486
        • Soultanakis HN
        • Artal R
        • Wiswell RA
        Prolonged exercise in pregnancy: glucose homeostasis, ventilatory and cardiovascular responses.
        Semin Perinatol. 1996; 20: 315-327
        • American College of Obstetrics and Gynecology
        Exercise during pregnancy and postpartum.
        (Washington (DC))February 1994 (ACOG Technical Bulletin No.: 189)
        • Lemon PWR
        Effects of exercise on dietary protein requirements.
        Int J Sports Nutr. 1998; 8: 426-447
        • Sady SP
        • Carpenter MW
        Aerobic exercise during pregnancy: special considerations.
        Sports Med. 1989; 7: 357-375
        • Lemon PWR
        • Yarasheski KE
        • Dolny DG
        Validity/reliability of sweat analysis by whole-body washdown vs. regional collections.
        J Appl Physiol. 1986; 61: 1967-1971
      1. Institute of Medicine. Nutrition during pregnancy. : National Academy Press, Washington (DC)1990
        • Artal R
        • Wiswell RA
        • Romem Y
        • Dorey F
        Pulmonary responses to exercise in pregnancy.
        Am J Obstet Gynecol. 1986; 154: 378-383
        • Knuttgen HG
        • Emerson K
        Physiological response to pregnancy at rest and during exercise.
        J Appl Physiol. 1974; 36: 549-553
        • Mougios V
        • Kotzamanidis C
        • Koutsari C
        • Atsopardis S
        Exercise-induced changes in the concentration of individual fatty acids and triacylglycerols of human plasma.
        Metabolism. 1995; 44: 681-688
        • Houghton PE
        • Mottola MF
        • Plust JH
        • Schachter CL
        Effect of maternal exercise on fetal and placental glycogen storage in the mature rat.
        Can J Appl Physiol. 2000; 25: 443-452
        • Kalhan SC
        • Gilfillan CA
        • Tserng KY
        • Savin SM
        Glucose-alanine relationship in normal human pregnancy.
        Metabolism. 1988; 37: 152-158
        • Felig P
        • Wahren J
        Influence of endogenous insulin secretion on splanchnic glucose and amino acid metabolism in man.
        J Clin Invest. 1971; 50: 1702-1711
        • Felig P
        • Wahren J
        Role of insulin and glucagons in the regulation of hepatic glucose production during exercise.
        Diabetes. 1979; 28: 71-75
        • Felig P
        Amino acid metabolism in man.
        Annu Rev Biochem. 1975; 44: 933-955
        • Dolny DG
        • Lemon PWR
        Effect of exercise on protein utilization during pregnancy [abstract].
        Can J Appl Sport Sci. 1986; 11 (11P)
        • Tarnopolsky MA
        • MacDougall JD
        • Atkinson SA
        • Tarnopolsky MA
        • Sutton JR
        Gender differences in substrate for endurance exercise.
        J Appl Physiol. 1990; 68: 302-308
        • Romem Y
        • Masaki DI
        • Artal RA
        Physiological and endocrine adjustments to pregnancy.
        in: 2nd ed. Exercise in pregnancy. : Williams and Wilkins, Baltimore1991: 9-29
        • Scott EM
        • McGarrigle HH
        • Lachelin GC
        The increase in plasma and saliva cortisol levels in pregnancy is not due to the increase in corticosteroid-binding globulin levels.
        J Clin Endocrinol Metab. 1990; 71: 639-644
        • Artal R
        • Platt LD
        • Sperling M
        • Kammula RK
        • Jilek J
        • Nakamura R
        Exercise in pregnancy.
        Am J Obstet Gynecol. 1981; 140: 123-127
        • Davis CTM
        • Few JD
        Effects of exercise on adrenocortical function.
        J Appl Physiol. 1973; 35: 887-891
        • Mazlan M
        • Spence-Jones C
        • Chard T
        • Landon J
        • McLean C
        Circulating levels of GH-releasing hormone and GH during human pregnancy.
        J Endocrinol. 1990; 125: 161-167
        • Jovanic L
        • Kessler A
        • Peterson CM
        Human and fetal response to graded exercise.
        J Appl Physiol. 1985; 58: 1719-1722