Dr Stephen Boutcher presented this emerging evidence and how it may be counteracted with aerobic exercise at a seminar organised by the Director of UNSW Sports Medicine Programs, Dr David Garlick. Dr Boutcher is a Sports Scientist from De Mountfort University, UK.

Although hyper-reactivity can be reduced through drug therapies, aerobic exercise (e.g., running, walking) is a more attractive strategy. It is inexpensive and has few negative side effects.

In healthy men and women regular aerobic exercise has been shown to result in lower absolute heart rates and their cardiovascular response to mental stress is improved. Other cardiovascular responses to stress such as cardiac output, peripheral resistance, and blood pressure have been found to be similar in trained and untrained healthy adults.

Thus, the greatest effect of increased exercise may be found in groups such as hypertensives. For example, a number of studies have indicated that a hyper-responsive defence reaction to stress is implicated in the development of hypertension. Repeated exposure to daily stressors may bring about an increased heart rate and cardiac output, heightened skeletal blood flow, and increased renal vasoconstriction. Over time these responses are believed to result in elevated total peripheral resistance with central responses returning to normal.

Our studies show that aerobically trained offspring of hypertensives had a significantly better cardiovascular response compared to a group of healthy male adults. The results show that aerobic exercise may reduce stress hyperactivity, however, it is not clear how it is reduced.

How exercise might bring about these effects is to be examined in a number of future studies. We will examine responses after acute aerobic exercise and exercise-related vasodilatory substances. We also intend to examine the influence of stress reactivity and exercise on adult-onset diabetes. It is feasible that continual hyper-reactivity to mental stressors causes insulin resistance. Regular aerobic exercise, in contrast, typically counteracts these effects.

Dr Boutcher’s visit to UNSW’s School of Physiology and Pharmacology was well received and his contribution to the health and sports science program greatly appreciated.