These are the conclussions of a work published in the last number of the Spanish Journal of Cardiology* carried out by the Research Group on Functional Assesment and Exercise Physiology of the University of Granada. In this work they have studied the impact of three different sports –swimming, volleyball and football- on total cholesterol plasmatic values, cholesterol LDL, cholesterol HDL, triglycerids, lipoprotein (a) and other lipid parameters, and they have observed that football and volleyball players, both of them stressful sports, present higher levels of cholesterol LDL (cLDL) -although within their reference range for their age and sex-, and lipoprotein (a) (Lp(a)), and, therefore, a lipid profile less favourable than swimmers, who present lower levels.
It is the first time that the role of the Lp(a) – which has been identified as an atherogenic and thrombogenic factor – and its interactions with other cardiovascular risk factors have been analysed. High intensity or stressful physical exercise increases Lp(a) values. We still do not know clinical importance of this finding; we know, however, from other studies, that when high Lp(a) levels join together with high cLDL levels cardiovascular risk increases exponentially. This association can be found more frequently in football and volleyball players, whereas it is non-existent in swimmers, probably due to the aerobic nature of swimming and the scarce or null contacts or falls.
Sportmen object of the study play competitive sports. “However – according to the authors – these results are very interesting for stressful sport amateur players with a high component of contacts and falls (football, rugby, basketball…) who intend to improve their physical condition doing sport just on weekends. Although we need more works to corroborate this theory, atherothrombosis risk would be higher in this population sector due to the lack of a continuous and well-planned training and the absence of factors which counteract the observed effects, like a higher antioxidant and fibrinolytic capacity which chacarterizes regular sportmen due to their better fitness.
“Meanwhile –Araceli Boraita, of the Department of Preventive Cardiology and Rehabilitation of the Spanish Society of Cardiology and cardiologist of the Sport Medicine Centre of the CSD -, ill persons suffering from dyslipemia should do an aerobic sport activity, of moderate intensity and over their life”.
The healthiest
The recognition of a sedentary lifestyle as a cardiovascular risk factor and the beneficial effect of the regular practice of physical exercise explain the promotion of sport in favour of health and disease prevention. “However – Dr. Boraita explains – not every physical activity has the same effects. The answer varies according to the sort of exercise, intensity, frequency, session length and stay time in the physical training program.”
With regard to atherosclerosis, a progressive disease characterized by the accumulation of lipids and fibrous elements in the large arteries, we know that the regular and moderate practice of aerobic exercise –swimming, cycling… – increases cHDL plasmatic values and reduces those of cLDL, and joins together with a healthy lipid-plasmatic profile and a lower risk coronary arteriopathy and cardiovascular mostality. However, these benefits can only be reached if certain conditions relating to training intensity and length are implemented.
Thus, when intensity is moderate, lipids kept in the organism are used as an energy source, and that use is higher as exercise length increases. However, when the exercise intensity is very high, free fatty acid availability as an energy-giving substratum reduces and the organism obtains energy from carbohydrates; this way the effects on the lipid profile are minimum.
Frequency is even more important than intensity, this is, the number of sessions done all through the week. “Taking into account that favourable effects – total cholesterol and cLDL reduction – remain for about 48 hours and afterwards they return to the initial values, a 30-60-minute exercise session every to days seems to be coherent to maintain such responses in time”, Dr. Boraita explains. With regards to cHDL increase, young persons manage to increase plasmatic levels after 6-12 months of practice. Those who are older than fifty need al least two years, although from the first moment they can obtain a slight fitness improvement and slight changes in their cHDL values.
• Ruiz JR et al. Stressful sports negatively affect plasmatic lipid profile. Rev Esp Cardiol 2004;57(6):499-506.
Further information: Press office of the Spanish Society of Cardiology
Maite Izquierdo. Phone number: 918 772 491
prensa@secardiologia.es
