According to a study published in the European Heart Journal, unfit lean men are less likely to have heart attacks than fit obese men. It was also discovered that the chances of heart attacks appeared to be reduced if physical fitness was maintained during teenage years.
The data of 743,498 Swedish men, who received a medical examination at the age of 18 when they were conscripted into national service between 1969 and 1984, was analysed by a team of Swedish professors and medical researchers from Umeå University. The team monitored the men's records until January 2011, or after the subjects suffered a heart attack, whichever came first. "While being physically fit at the end of your teens can reduce the risk of heart attack, fitness alone does not appear to fully compensate for the risks with being overweight or obese. In other words, having a normal weight is more important than being in good physical shape, but it is even better to be both fit and have a normal weight," said Peter Nordström, one of the researchers.
The results indicated that exercise late into teenage years reduced the risk of a premature heart attack by 35 percent. Additionally -- after factoring in a number of variables such as BMI, and economic and social backgrounds -- with each 15 percent increase of fitness, the chances of having a heart attack in 30 years time was reduced by a further 18 percent. "The heart attack risk was reduced by about 35 percent among lean men and those with a normal weight at the end of their teens. But the study only shows that there is a correlation between fitness and a reduced prevalence of heart attack; we were unable to show specifically that a higher level of physical fitness reduces the risk of heart attacks," said Nordström.
Nordström emphasised that the connection between fitness and heart disease is complex and can be influenced by a large number of other sources. Some people are genetically predisposed to a high level of fitness with a low risk of heart failure, for example.
Nordström hopes his research will aid the planning of preventative public health programmes.