Skip to main content

Alterations in Energy Metabolism During Exercise and Heat Stress

Abstract

Much of the research that has examined the interaction between metabolism and exercise has been conducted in comfortable ambient conditions. It is clear, however, that environmental temperature, particularly extreme heat, is a major practical issue one must consider when examining muscle energy metabolism. When exercise is conducted in very high ambient temperatures, the gradient for heat dissipation is significantly reduced which results in changes to thermoregulatory mechanisms designed to promote body heat loss. This can ultimately impact upon hormonal and metabolic responses to exercise which act to alter substrate utilisation. In general, the literature examining metabolic responses to exercise and heat stress has demonstrated a shift towards increased carbohydrate use and decreased fat use. Although glucose production appears to be augmented during exercise in the heat, glucose disposal and utilisation appears to be unaltered. In contrast, glycogen use has been consistently demonstrated to be augmented during exercise in the heat. This increase in glycogenolysis is observed via both aerobic and anaerobic pathways. Although several hypotheses have been proposed as mechanisms for the substrate shift towards greater carbohydrate metabolism during exercise and heat stress, recent work suggests that an augmented sympatho-adrenal response and intramuscular temperature may be responsible for such a phenomenon.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

References

  1. 1.

    Buskirk ER. Temperature regulation with exercise. Exerc Sport Sci Rev 1997; 5: 45–88

    Google Scholar 

  2. 2.

    Gisolfi CV, Wenger CB. Temperature regulation during exercise: old concepts, new ideas. Exerc Sport Sci Rev 1984; 12: 339–72

    PubMed  Article  CAS  Google Scholar 

  3. 3.

    Nadel ER. Recent advances in temperature regulation during exercise in humans. Fed Proc 1985; 44 (7): 2286–92

    PubMed  CAS  Google Scholar 

  4. 4.

    Rowell LB. Human cardiovascular adjustments to exercise and thermal stress. Physiol Rev 1974; 54: 75–159

    PubMed  CAS  Google Scholar 

  5. 5.

    Sawka MN, Coyle EF. Influence of body water and blood volume on thermoregulation and exercise performance in the heat. Med Sci Sports Exerc 1999; 27: 167–218

    CAS  Google Scholar 

  6. 6.

    Fink WJ, Costill DL, Van Handel PJ. Leg muscle metabolism during exercise in the heat and cold. Eur J Appl Physiol 1975; 34:183–90

    Article  CAS  Google Scholar 

  7. 7.

    Febbraio MA, Snow RJ, Hargreaves M, et al. Muscle metabolism during exercise and heat stress in trained men: effect of acclimation. J Appl Physiol 1994; 76: 589–97

    PubMed  CAS  Google Scholar 

  8. 8.

    Febbraio MA, Snow RJ, Stathis CG, et al. Effect of heat stress on muscle energy metabolism during exercise. J Appl Physiol 1994; 77: 2827–31

    PubMed  CAS  Google Scholar 

  9. 9.

    Hargreaves M, Angus D, Howlett K, et al. Effect of heat stress on glucose kinetics during exercise. J Appl Physiol 1996; 81: 1594–97

    PubMed  CAS  Google Scholar 

  10. 10.

    King DS, Costill DL, Fink WJ, et al. Muscle metabolism during exercise in the heat in unacclimatized and acclimatized humans. J Appl Physiol 1985; 59 (5): 1350–4

    PubMed  CAS  Google Scholar 

  11. 11.

    Kirwan JP, Costill DL, Kuipers H, et al. Substrate utilization in leg muscle of men after heat acclimation. J Appl Physiol 1987; 63: 31–5

    PubMed  CAS  Google Scholar 

  12. 12.

    Young A.J, Sawka MN, Levine L, et al. Skeletal muscle metabolism during exercise is influenced by heat acclimation. J Appl Physiol 1985; 59: 1929–35

    PubMed  CAS  Google Scholar 

  13. 13.

    Gonzalez-Alonso J, Calbet JAL, Nielsen B. Metabolic and thermodynamic responses to dehydration-induced reductions in blood flow in exercising humans. J Physiol 1999; 520: 577–89

    PubMed  Article  CAS  Google Scholar 

  14. 14.

    Hargreaves M, Dillo P, Angus D, et al. Effect of fluid ingestion on muscle metabolism during prolonged exercise. J Appl Physiol 1996; 80: 363–6

    PubMed  CAS  Google Scholar 

  15. 15.

    Febbraio MA, Snow RJ, Stathis CG, et al. Blunting the rise in body temperature reduces muscle glycogenolysis during exercise in humans. Exp Physiol 1996; 81: 685–93

    PubMed  CAS  Google Scholar 

  16. 16.

    Parkin JM, Carey MF, Zhao S, et al. Effect of ambient temperature on human skeletal muscle metabolism during fatiguing submaximal exercise. J Appl Physiol 1999; 86: 902–8

    PubMed  Article  CAS  Google Scholar 

  17. 17.

    Kozlowski S, Brzezinska Z, Kruk B, et al. Exercise hyperthermia as a factor limiting physical performance: temperature effect on muscle metabolism. J Appl Physiol 1985: 59:766–73

    PubMed  CAS  Google Scholar 

  18. 18.

    Maxwell NS, Gardner F, Nimmo MA. Intermittent running: muscle metabolism in the heat and effect of hypohydration. Med Sci Sports Exerc 1999: 31: 675–83

    PubMed  Article  CAS  Google Scholar 

  19. 19.

    Nielsen B, Savard G, Richter EA, et al. Muscle blood flow and muscle metabolism during exercise and heat stress. J Appl Physiol 1990: 69: 1040–6

    PubMed  CAS  Google Scholar 

  20. 20.

    Yaspelkis III BB, Scroop GC, Wilmore KM, et al. Carbohydrate metabolism during exercise in hot and thermoneutral environments. Int J Sports Med 1993; 14: 13–9

    PubMed  Article  Google Scholar 

  21. 21.

    Young AJ, Sawka MN, Levine L, et al. Metabolic and thermal adaptations from endurance training in hot and cold water. J Appl Physiol 1995; 78: 793–801

    PubMed  CAS  Google Scholar 

  22. 22.

    Chesley A, Hultman E, Spriet LL. Effects of epinephrine infusion on muscle glycogenolysis during intense aerobic exercise. Am J Physiol 1995; 268 (1 Pt 1): E127–34

    PubMed  CAS  Google Scholar 

  23. 23.

    Hargreaves M, McConell G, Proietto J. Influence of muscle glycogen on glycogenolysis and glucose uptake during exercise in humans. J Appl Physiol 1995; 78: 288–92

    PubMed  Article  CAS  Google Scholar 

  24. 24.

    Hespel, P, Richter EA. Mechanisms linking glycogen and glycogenolytic rate in perfused contracting rat skeletal muscle. Biochem J 1992; 284: 777–80

    PubMed  CAS  Google Scholar 

  25. 25.

    Rowell LB, Brengelmann GL, Blackmon JR, et al. Splanchnic blood flow and metabolism in heat stressed man. J Appl Physiol 1968; 24: 475–84

    PubMed  CAS  Google Scholar 

  26. 26.

    Dolny DG, Lemon PWR. Effect of ambient temperature on protein breakdown during prolonged exercise. J Appl Physiol 1988; 64: 550–5

    PubMed  CAS  Google Scholar 

  27. 27.

    Wendling PS, Peters SJ, Heigenhauser GJF, et al. Variability of triacylglecerol content in human skeletal muscle biopsy samples. J Appl Physiol 1996; 81: 1150–5

    PubMed  CAS  Google Scholar 

  28. 28.

    Snow RJ, Febbraio MA, Carey ME, et al. Heat stress increases ammonia accumulation during exercise. Exp Physiol 1993; 78: 847–50

    PubMed  CAS  Google Scholar 

  29. 29.

    Graham TE, Rush JWE, MacLean DA. Skeletal muscle amino acid metabolism and ammonia production during exercise. In: Hargreaves M, editor. Exercise metabolism. Champaign (IL): Human Kinetics, 1995: 131–76

    Google Scholar 

  30. 30.

    Febbraio MA, Murton P, Selig SE, Clark SA, Lambert DL, Angus DJ, Carey MF. Effect of CHO ingestion on exercise metabolism and performance in different ambient temperatures. Medicine and Science in Sports and Exercise 1996 28: 1380–7

    PubMed  Article  CAS  Google Scholar 

  31. 31.

    Kjær M. Hepatic fuel metabolism during exercise. In: Hargreaves M, editor. Exercise metabolism. Champaign (IL): Human Kinetics, 1995: 73–97

    Google Scholar 

  32. 32.

    Jeukendrup AE, Wagenmakers AIM, Stegen JH, et al. Carbohydrate ingestion can completely suppress endogenous glucose production during exercise. Am J Physiol 1999; 276 (4 Pt 1): E672–83

    Google Scholar 

  33. 33.

    McConell G, Fabris S, Proietto J, et al. Effects of carbohydrate ingestion on glucose kinetics during exercise. J Appl Physiol 1994; 77: 1537–41

    PubMed  CAS  Google Scholar 

  34. 34.

    Howlett K, Angus DJ, Proietto J, et al. Effect of increased blood glucose availability on glucose kinetics during exercise. J Appl Physiol 1998; 84: 1413–7

    PubMed  CAS  Google Scholar 

  35. 35.

    Angus DJ, Febbraio MA, Lasini D, et al. Effect of carbohydrate ingestion on glucose kinetics during exercise in the heat. J Appl Physiol. In press

  36. 36.

    Sawka MN, Young AJ, Caderette BS, et al. Influence of heat stress and acclimation on maximal aerobic power. Eur J Appl Physiol 1984; 53: 294–8

    Article  Google Scholar 

  37. 37.

    Rowell LB, Blackmon JR, Martin RH, et al. Hepatic clearance of indocyanine green in man under thermal and exercise stresses. J Appl Physiol 1965; 20: 384–94

    PubMed  CAS  Google Scholar 

  38. 38.

    Radigan LR, Robinson S. Effect of environmental heat stress and exercise on renal blood flow and filtration rate. J Appl Physiol 1949; 2: 185–91

    PubMed  CAS  Google Scholar 

  39. 39.

    Rowell LB. Human circulation: regulation during physical stress. New York: Oxford University Press, 1986

    Google Scholar 

  40. 40.

    Rowell LB, O’Leary DS, Kellogg DL Jr. Integration of cardiovascular control systems in dynamic exercise. In: Rowell LB, Shepherd IT, editors. Handbook of physiology. Section 12. Exercise: regulation and integration of multiple systems. New York: Oxford University Press, 1996

    Google Scholar 

  41. 41.

    Young AJ. Energy substrate utilization during exercise in extreme environments. Exerc Sports Sci Rev 1990; 18: 65–117

    Article  CAS  Google Scholar 

  42. 42.

    Bell A, Hales J, King R, et al. Influence of heat stress on exercise-induced changes in regional blood flow in sheep. J Appl Physiol 1983; 55: 1916–23

    PubMed  CAS  Google Scholar 

  43. 43.

    Nielsen B, Hales JRS, Strange S, et al. Human circulatory and thermoregulatory adaptations with heat acclimation and exercise in a hot, dry environment. J Physiol 1993; 460: 467–85

    PubMed  CAS  Google Scholar 

  44. 44.

    Nielsen B, Strange S, Christensen NJ, et al. Acute and adaptive responses in humans to exercise in a warm, humid environment. Pflügers Arch 1997; 434 (1): 49–56

    PubMed  Article  CAS  Google Scholar 

  45. 45.

    Savard GK, Nielsen B, Laszczynska J, et al. Muscle blood flow is not reduced in humans during moderate exercise and heat stress. J Appl Physiol 1988; 64: 649–57

    PubMed  CAS  Google Scholar 

  46. 46.

    Smolander J, Louhevaara V. Effects of heat stress on muscle blood flow during dynamic handgrip exercise. Eur J Appl Physiol 1992; 65: 215–20

    Article  CAS  Google Scholar 

  47. 47.

    Gonzalez-Alonso J, Calbet JAL, Nielsen B. Muscle blood flow is reduced with dehydration during prolonged exercise in humans. J Physiol 1999; 513: 895–905

    Article  Google Scholar 

  48. 48.

    Gonzalez-Alonso J, Mora-Rodriguez R, Below PR, et al. Dehydration markedly impairs cardiovascular function in hyperthermic endurance athletes during exercise. J Appl Physiol 1997; 82: 1229–36

    PubMed  CAS  Google Scholar 

  49. 49.

    Schumacker PT, Rowland J, Saltz S, et al. Effects of hyperthermia and hypothermia on oxygen extraction by tissues during hypovolemia. J Appl Physiol 1987; 63: 1246–52

    PubMed  CAS  Google Scholar 

  50. 50.

    Clarke MG, Colqhoun EQ, Rattigan S, et al. Vascular and endocrine control of muscle metabolism. Am J Physiol 1995; 268:E797–812

    Google Scholar 

  51. 51.

    Gollnick PD, Armstrong RB, Saubert CW 4th, et al. Glycogen depletion patterns in human skeletal muscle fibres during prolonged work. Pflügers Arch 1973; 344 (1): 1–12

    PubMed  Article  CAS  Google Scholar 

  52. 52.

    Saltin B, Hermansen L. Esophageal, rectal and muscle temperature during exercise. J Appl Physiol 1966; 21: 1757–62

    PubMed  CAS  Google Scholar 

  53. 53.

    Florkin M, Stoltz EH. Comprehensive biochemistry. 12. New York: Elselvier, 1968

    Google Scholar 

  54. 54.

    Edwards RHT, Harris RC, Hultman E, et al. Effect of temperature on muscle energy metabolism and endurance during successive isometric contractions, sustained to fatigue, of the quadriceps muscle in man. J Physiol 1972; 220: 335–52

    PubMed  CAS  Google Scholar 

  55. 55.

    Galbo H, Houston ME, Christensen NJ, et al. The effect of water temperature on the hormonal response to prolonged swimming. Acta Physiol Scand 1979; 105 (3): 326–37

    PubMed  Article  CAS  Google Scholar 

  56. 56.

    Powers SK, Howley ET, Cox R. Blood lactate concentrations during submaximal work under differing environmental conditions. J Sports Med Phys Fitness 1985; 25 (3): 84–9

    PubMed  CAS  Google Scholar 

  57. 57.

    Greenhaff PL, Ren J-M, Söderlund K, et al. Energy metabolism in single human muscle fibers during contractions with and without epinephrine infusion. Am J Physiol 1991; 260 (2 Pt 1): E713–8

    Google Scholar 

  58. 58.

    Jansson E, Hjemdahl P, Kaijser L. Epinephrine induced changes in muscle carbohydrate metabolism during exercise in male subjects. J Appl Physiol 1986; 60: 1466–70

    PubMed  CAS  Google Scholar 

  59. 59.

    Spriet LL, Ren J-M, Hultman E. Epinephrine infusion enhances muscle glycogenolysis during prolonged electrical stimulation. J Appl Physiol 1988; 64: 1439–44

    PubMed  CAS  Google Scholar 

  60. 60.

    Febbraio MA, Carey MF, Snow RJ, et al. Influence of elevated muscle temperature on metabolism during intense, dynamic exercise. Am J Physiol 1996; 271: R1251–5

    Google Scholar 

  61. 61.

    Starkie RL, Hargreaves M, Lambert DL, et al. Effect of temperature on muscle metabolism during submaximal exercise. Exp Physiol 1999; 84: 775–84

    PubMed  Article  CAS  Google Scholar 

  62. 62.

    Uyeda K. Phosphofructokinase. Adv Enzymol Relat Areas Mol Biol 1979; 48: 193–244

    PubMed  CAS  Google Scholar 

  63. 63.

    Ren J-M, Hultman E. Regulation of phosphorylase a activity in human skeletal muscle. J Appl Physiol 1990; 67: 919–23

    Google Scholar 

  64. 64.

    Galbo H. Hormonal and metabolic adaptations to exercise. New York: Thiemme-Stratton Inc., 1983

    Google Scholar 

  65. 65.

    Richter EA, Ruderman NB, Gavras H, et al. Muscle glycogenolysis during exercise: dual control by epinephrine and contractions. Am J Physiol 1982; 242 (1): E25–32

    Google Scholar 

  66. 66.

    Richter EA, Sonne B, Christensen NJ, et al. Role of epinephrine for muscular glycogenolysis and pancreatic hormone secretion in running rats. Am J Physiol 1981; 240 (5): E526–32

    Google Scholar 

  67. 67.

    Issekutz, B. Effect of epinephrine on carbohydrate metabolism in exercising dogs. Metabolism 1985; 34: 457–64

    PubMed  Article  CAS  Google Scholar 

  68. 68.

    Hashimoto I, Knudson MB, Noble EG, et al. Exercise-induced glycogenolysis in sympathectomized rats. Jpn J Physiol 1982; 32: 153–60

    PubMed  Article  CAS  Google Scholar 

  69. 69.

    Issekutz B. Effect of β-adrenergic blockade on lactate turnover in exercising dogs. J Appl Physiol 1984; 57: 1754–59

    PubMed  CAS  Google Scholar 

  70. 70.

    Wendling PS, Peters SJ, Heigenhauser GJF, et al. Epinephrine infusion does not enhance net muscle glycogenolysis during prolonged aerobic exercise. Can J Appl Physiol 1996; 21: 271–84

    PubMed  Article  CAS  Google Scholar 

  71. 71.

    Febbraio MA, Lambert DL, Starkie RL, et al. Effect of epinephrine on muscle glycogenolysis during exercise in trained men. J Appl Physiol 1998; 84: 465–70

    PubMed  CAS  Google Scholar 

  72. 72.

    Turner MJ, Howley ET, Tanaka H, et al. Effect of graded epinephrine infusion on blood lactate response to exercise. J Appl Physiol 1995; 79: 1206–11

    PubMed  CAS  Google Scholar 

  73. 73.

    Putman CT, Spriet LL, Hultman E, et al. Pyruvate dehydrogenase activity and acetyl group accumulation during exercise after different diets. Am J Physiol 1993; 265 (5 Pt 1): E752–60

    Google Scholar 

  74. 74.

    Martin WH III. Effects of acute and chronic exercise on fat metabolism. Exerc Sports Sci Rev 1996; 24: 203–31

    Article  Google Scholar 

  75. 75.

    Cooper DM, Wasserman DW, Vranic M, et al. Glucose turnover in response to exercise during high- and low FIO2 breathing in man. Am J Physiol 1986; 251: E209–14

    Google Scholar 

  76. 76.

    Kjær M, Kiens B, Hargreaves M, et al. Influence of active muscle mass on glucose homeostasis during exercise in humans. J Appl Physiol 1991; 71: 552–7

    PubMed  Google Scholar 

  77. 77.

    Sonne B, Mikines KJ, Richter EA, et al. Role of liver nerves and adrenal medulla in glucose turnover in running rats. J Appl Physiol 1985; 59: 1640–6

    PubMed  CAS  Google Scholar 

  78. 78.

    Kjær M, Engfred K, Fernandes A, et al. Regulation of hepatic glucose production during exercise in humans: role of sympathoadrenergic activity. Am J Physiol 1993; 265 (2 Pt 1): E275–83

    Google Scholar 

  79. 79.

    Kjær M, Keiding S, Engfred K, et al. Glucose homeostasis during exercise in humans with a liver or kidney transplant. Aim J Physiol 1995; 268 (4 Pt 1): E636–44

    Google Scholar 

  80. 80.

    Howlett K, Febbraio MA, Hargreaves M. Liver glucose production during strenuous exercise in humans: role of epinephrine. Am J Physiol 1999; 276 (6 Pt 1): E1130–5

    Google Scholar 

  81. 81.

    Howlett K, Galbo H, Lorentsen J, et al. Effect of adrenaline on glucose kinetics during exercise in adrenalectomised humans. J Physiol 1999; 519: 911–21

    PubMed  Article  CAS  Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Mark A. Febbraio.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Febbraio, M.A. Alterations in Energy Metabolism During Exercise and Heat Stress. Sports Med 31, 47–59 (2001). https://doi.org/10.2165/00007256-200131010-00004

Download citation

Keywords

  • Heat Stress
  • Hepatic Glucose Production
  • Muscle Blood Flow
  • Lactate Accumulation
  • Cool Environment