Bernard Marti

Development of Public Policy and Physical Activity Initiatives Internationally

SummaryEpidemiological, pathological, clinical, and experimental studies over the past 40 years convincingly show that physical inactivity and low physical fitness contribute substantially to the major chronic diseases prevalent in industrialised societies. Several industrialised countries around the world report increases in physical activity participation among adults in recent years, but the prevalence of inactivity remains high. These increases in voluntary exercise are at least partially offset by decreasing daily energy demands due to increased mechanisation at home, at work and during leisure-time. In developing countries, physical inactivity is becoming a prevalent lifestyle due to rapid social and economic changes.Clinical interventions and mass appeals to be more physically active are limited in effectiveness against the background of increasingly sedentary lifestyles. Exercise scientists and public health officials need to turn attention to public policy and legislative initiatives to restructure physical and social environments to encourage more physical activity and discourage sedentary habits.

Health effects of recreational running in women. Some epidemiological and preventive aspects.

SummaryEstimated maximum oxygen uptake of middle-aged nonelite road race entrants is around 45 to 50 ml/kg/min, which is 40 to 100% higher than values from the female general population. Endurance training, low bodyweight, and nonsmoking of runners explain part of, but not the whole, difference in aerobic capacity observed between athletes and the general population. Sedentary women can improve cardiorespiratory fitness through aerobic exercise programmes, and the women with the lowest level of initial fitness have the highest proportional improvement following training. Regularly exercising women have a significantly reduced risk of fatal and nonfatal coronary events, and low cardiorespiratory fitness is associated with an increased risk of death and nonfatal stroke. The influence of habitual running on the female blood lipid profile is not clear. Cross-sectional studies have found elevated HDL cholesterol concentrations in distance runners, but intervention studies on the effect of jogging on lipid and lipoprotein levels have provided equivocal results. A higher level of physical fitness is associated with a lower risk to subsequently develop hypertension. Experimental studies have shown that moderate intensity aerobic exercise (40 to 60% V̇O2max) is able to reduce blood pressure significantly in hypertensive subjects. An athletic lifestyle may be associated with a reduced risk of adult-onset diabetes mellitus (via an exercise-induced increase in insulin sensitivity), and with a reduced risk of cancers of the reproductive system, breast, and colon. Recreational running is also correlated with better weight control.Surveys of recreational and elite distance runners show a great variability in the prevalence of secondary amenorrhoea, between 1 and 44%. Environmental factors determining the risk of amenorrhoea in runners are low body fat content, mileage, and nutritional inadequacy, with low intakes of calories, protein, and fat. Amenorrhoeic athletes in their third and fourth decade have lower vertebral bone density, which is improved after resumption of menses but does not completely reach age-specific average values. Regardless of menstrual status, the effectiveness of exercise to maintain bone mass throughout life is an important issue. Habitual exercise is associated with increased bone density of the spine both in premenopausal and postmenopausal women. Several controlled training studies suggest that postmenopausal women may at least retard their bone loss with regular aerobic exercise.Running-related injuries and complaints are common in recreational joggers, even though the reported 1-year incidence, varying between 14 and approximately 50%, depends on injury definition. Mileage and a history of previous running injury are known risk factors. Overweight, irregular menses, and absence of oral contraceptive use have been identified as risk factors in single studies. Female gender itself does not seem to be a major risk factor of running injuries among habitually active subjects, but it may be a relevant factor for sedentary subjects taking up jogging. Regarding the effect of habitual running on the development of osteoarthritis in weight-bearing joints, available data suggest that reasonable recreational exercise, carried out within limits of comfort, putting joints through normal motions, without underlying joint abnormality, even over many years, is unlikely to lead to significant joint injury.Habitual exercise is associated with reductions in anxiety and depression as well as increased self-esteem. The latter is an empirically supported outcome of exercise, and programmes of aerobic exercise seem also to be effective in reducing state anxiety and symptoms of mild depression. The prevalence of anorexia nervosa among competitive distance runners is not higher than among the general population, but it is the best runners who are most likely to be anorectic. Nonsmoking is highly prevalent among runners, and habitual runners who smoke have a quit rate of roughly 75%, with the rate of smoking cessation being related to mileage. Compared with the general population, age-matched runners have significantly fewer medical consultations, and probably less missed work days.Little data on the health effects of recreational, in contrast to competitive, running is available, and most epidemiological studies on prevention through exercise suffer from methodological shortcomings that hamper the ability to evaluate the health potential of aerobic exercise in an unbiased way. Nevertheless, there is a broad consensus that an energy expenditure of at least 150 to 400 kcal/day (corresponding to jogging 2.5 to 6 km/day) at a moderate intensity, should be the goal for health-oriented exercise.

Effects of long-term, self-monitored exercise on the serum lipoprotein and apolipoprotein profile in middle-aged men

To study the effects of long-term, self-monitored exercise on the serum lipid profile and body composition of middle-aged non-smoking males, a controlled study was conducted in 61 sedentary, middle-class Swiss men. Thirty-nine men were randomly allocated to jog 2 h/wk for 4 months on an individually prescribed, heart rate-controlled basis, whereas 22 men served as controls. Despite varying adherence to the exercise regimen, the following 4-month net changes (effect in exercise group minus effect in control group) in lipids were seen: HDL cholesterol (C) +0.12 mmol/l (95% CI 0.02, 0.22; P = 0.028), LDL-C +0.08 mmol/l (ns), VLDL-C -0.26 mmol/l (-0.45, -0.07; P = 0.009), total triglycerides (TT) -0.21 mmol/l (ns), HDL-C/total C +0.02 (0.001, 0.05; P = 0.047). The net changes in endurance capacity and resting heart rate in favour of exercisers were significant as well, whereas no significant changes in apolipoprotein levels were seen. Exploratory analyses revealed, for example, associations of the increase in total physical activity with an increase in the HDL-C/total C ratio (r = 0.46; P less than 0.001), and of the change in estimated body fat content with an opposed change in the HDL-C/total C ratio (r = -0.40; P less than 0.001), or an inverse relationship of the change in subcutaneous fat with a change in the HDL2-C level (r = -0.39; P less than 0.001). Multivariable regression analysis suggested that much of the effect of jogging on HDL-C was apparently mediated through a decrease in body fat content. A change in the waist/hip ratio was unrelated to lipoprotein changes but was related to the change of TT level (r = 0.22; P less than 0.05). This study confirms that individually prescribed, unsupervised jogging can increase HDL-C levels and improve the serum lipoprotein profile in self-selected nonsmoking males. Although the effect is modest, it may be relevant to preventive cardiology, given the evidence for a reduction in cardiovascular risk even after apparently small decreases in risk factor levels.

The public perception of doping in sport in Switzerland, 1995 – 2004

Abstract The article reports findings on the perception of doping and anti-doping policies from four representative population surveys carried out in 1995, 1998, 2001, and 2004, as well as from a 2005 – 2006 survey of top-level athletes in Switzerland. The results show a growing public awareness for doping issues and increasing support for a comprehensive anti-doping strategy in Switzerland. The vast majority of the Swiss population and top-level athletes are strongly against doping and support a strategy that combines strict prohibition and sanctioning with informational and educational efforts. The perception of the doping issue and the strategic preferences in fighting doping stated by the public are largely in line with the current anti-doping strategy followed by the Swiss authorities. The results thus suggest a successful use of information resources by the authorities to create public awareness and to communicate its strategy.

Anthropometric and lifestyle correlates of serum lipoprotein and apolipoprotein levels among normal non-smoking men and women

The relationship between serologic predictors of coronary risk and anthropometric as well as lifestyle characteristics was investigated in 61 men (37.5 +/- 8.5 yrs) and 33 women (40.1 +/- 9.0 yrs). All subjects were healthy non-smokers, mostly middle-class bank employees. In bivariate analysis, among both genders the ratio of waist-to-hip circumference (WHR) was the single best predictor of levels of serum LDL-cholesterol, apolipoprotein B, VLDL-cholesterol and triglycerides (positive association) as well as HDL-cholesterol and apolipoprotein A-I (inverse association). In men, body fat as estimated from bioelectrical impedance measurement was the second best predictor of lipoprotein and apoprotein concentrations, whereas in women it was the body mass index (BMI). The additional independent predictive power of WHR and body fat for the lipid profile was tested in multivariate analysis by adding WHR and body fat sequentially to regression models containing already BMI, endurance capacity, exercise, alcohol consumption and age. For example, explained variance of triglyceride distribution rose from 26.3 to 35.1% (P = 0.01 for increase) when body fat was entered into the regression equation, or inclusion of WHR into a model already containing age, the behavioral variables, BMI, and body fat increased the explained variance of LDL/HDL-cholesterol ratio from 20.9 to 27.6% (P = 0.04 for increase). In women, the same regression models were even slightly more predictive for the serum lipid profile. Endurance capacity was related to a low atherogenic risk lipid profile in bivariate analysis but lost much of its predictive power in multivariate analysis, which confirms that the effect of fitness on lipid levels is probably mediated in part by a low body fat content. It is concluded from this cross-sectional investigation that studies which focus on associations between lifestyle and serologic predictors of atherogenic risk should possibly include the WHR and a measure of body fat, since the latter two appear to be closer correlates of serum lipoprotein and apolipoprotein levels than BMI or single behavioral factors, at least among male non-smokers.

Fifteen-year changes in exercise, aerobic power, abdominal fat, and serum lipids in runners and controls

To describe effects of past as well as current exercise, aerobic power, and subcutaneous fat on the serum lipid profile, two groups of former elite athletes (N = 27 runners, N = 9 bobsledders) and a control group of normal men (N = 23) were investigated. Analysis of variance indicated a significant effect of the type of sports activity on HDL cholesterol, apolipoprotein A-I, and triglyceride levels and on the LDL/HDL cholesterol and apolipoprotein B/A-I ratios, with the most favorable values seen in runners and the least favorable values seen in controls. Of the 27 former elite runners, one third (N = 9) had given up or strongly reduced training. This subgroup showed the steepest 15-yr decrease (from 1973 to 1988) in maximum aerobic power and the largest 15-yr increase in subcutaneous fat, and the lipid profile (measured in 1988) corresponded more to the one of bobsledders and controls than to the one of runners who had remained active. Separate correlational analyses of all runners (N = 27) and nonrunners (N = 32) showed that, in both cohorts, i) the 1988 measurements of exercise, aerobic power, and subcutaneous fat were more predictive for the lipid profile in 1988 than the corresponding 1973 values, ii) anthropometric characteristics, especially abdominal fat, had a stronger relation with serum lipid concentrations than exercise and aerobic power, and iii) 15-yr changes in anthropometric characteristics were, but 15-yr changes in exercise and aerobic power were not, associated with triglyceride, lipoprotein, and apolipoprotein levels in 1988.(ABSTRACT TRUNCATED AT 250 WORDS)

Bedeutung der Lebensstilfaktoren für das Blutfettprofil von Bankangestellten

In a study sample of 75 sedentary, non-smoking male bank employees (mean age 41.2 +/- 7.8 years) the relationship between lifestyle characteristics and serum lipid concentrations were examined. According to the mortality statistics of the canton of Zurich, this population is at increased risk for coronary heart disease. Statistical analyses confirmed the predictive character of physical activity for serum lipid levels. A low level of physical activity was associated with significantly higher concentrations of apolipoprotein B and LDL-C (Pearson coefficient of correlation r = -0.38, p < 0.001 and r = -0.35, p < 0.01, respectively). Accumulation of upper body fat (estimated by the waist to hip ratio) revealed to be a better predictor of lipid levels than body mass index and showed highly significant positive correlations with atherogenic lipid fractions. The most pronounced differences were seen for triglyceride levels, where the subgroup of subjects in the lowest tertile of waist-hip ratio showed about 40% lower triglyceride values compared to the highest waist-hip ratio tertile. In a study population of self-selected, non-smoking men, high levels of LDL-C and apolipoprotein B could partially be explained by unfavourable life style characteristics, particularly physical inactivity. The waist-hip ratio, characterizing abdominal fat accumulation, proved to be a good indicator of an atherogenic lipid profile. Measuring waist-hip ratio in medical routine examinations should thus be considered.