Long-term recreational gymnastics provides a clear benefit in age-related functional decline and bone loss. A prospective 6-year study.

INTRODUCTION: Bone fragility and decreased functional performance are risk factors for osteoporotic fractures. The influence of long-term recreational gymnastics on the maintenance of bone rigidity and physical performance was evaluated. METHODS: One hundred and seven gymnasts and 110 referents (93% of the original sample) participated in this 6-year prospective study. Analysis of covariance (ANCOVA) was used to estimate the between-group differences and changes by time, and regression analyses to find predictors for changes. RESULTS: In both groups agility and leg extensor power decreased by over 3% and 10%, respectively, but the original between-group differences, favoring the gymnasts, persisted. Proximal femur bone mineral content (BMC) decreased approximately 0.5% per year in both groups, and femoral neck section modulus decreased. Trabecular density of the distal tibia declined only marginally, and cortical area of the tibial midshaft remained unchanged, while cortical density decreased about 2% in both groups. After adjustment by age, height, weight, change in weight, and follow-up time, antiresorptive medication and high calcium intake accounted most for the maintenance of bone rigidity. CONCLUSIONS: In spite of similar rates of decline in bone characteristics and physical performance, the recreational gymnasts' overall physical condition was comparable to the level that their less active referents had shown approximately 5 years earlier.

Sudden cardiac death due to physical exercise in male competitive athletes. A report of six cases.

In the period of 30 years, i.e. from 1973 to 2002, we noticed in Croatia 6 sudden and unexpected cardiac deaths in male athletes during or after training. Two were soccer players, 2 athletic runners, one was a rugby player and one was a basketball player. All of them were without cardiovascular symptoms. At the forensic autopsy, the first athlete, aged 29, had chronic myocarditis and thickened left ventricular wall of 15 mm. The second, aged 21, had an acute myocardial infarction of the posterior wall with normal coronaries and thickened left ventricular wall of 15 mm. The third aged 17, had hypoplastic right coronary artery and narrowed ascending aorta, suppurant tonsillitis and subacute myocarditis. Two athletes, aged 29 and 15, had hypertrophic cardiomyopathy and normal coronaries, and one dilated aorta. The sixth, aged 24, had arrhythmogenic cardiomyopathy of the right ventricle. All the 6 athletes died suddenly, obviously because of malignant ventricular arrhythmias. In Croatia the death rate among athletes reached 0.15/100 000, in others who practice exercise reached 0.74/100,000 and the difference is highly significant (c2=14.487, Poisson rates=3.81, P=0.00014) and in physicians-specialists reached 33.6/100,000. Preventive medical examinations are essential, especially in athletes before physical exercise, as are other investigations in every case suspicious of heart disease, including electrocardiogram (ECG), stress ECG, echocardiography and stress-echocardiography and other findings if indicated. Physical exercise is contraindicated in acute respiratory infection: in 2 of those cases had been a cause of death as a trigger.

Circulating oxidized low-density lipoprotein and common carotid artery intima-media thickness in a random sample of middle-aged men.

Circulating oxidized low-density lipoprotein (oxLDL) has been suggested to play an important role in atherosclerosis development. According to previous observations, oxLDL correlates with clinically manifest coronary and carotid artery disease. We investigated the association between the oxLDL concentration measured directly in plasma and common carotid artery intima-media thickness (IMT) in a population-based, case-control study in middle-aged men from Southern Finland. oxLDL was determined in 214 men by a commercially available sandwich ELISA test (Mercodia). Carotid artery IMT was measured at 12 standardized segments by B-mode ultrasonography (at the near and far wall of the left and right common carotid arteries, bifurcations and internal carotid arteries), and the overall mean maximum IMT (MMaxIMT) was calculated. The MMaxIMT of the carotid arteries was significantly associated with circulating oxLDL (r(s) = 0.16, p = 0.018). In a stepwise multiple regression model with MMaxIMT as dependent variable and systolic blood pressure, smoking, oxLDL, HDL cholesterol and apolipoprotein B as covariates, systolic blood pressure (beta = 0.22, p < 0.001), oxLDL (beta = 0.15, p = 0.022) and smoking (beta = 0.17, p = 0.014) showed an independent association with IMT (R(2) = 0.10, p < 0.001). Our results show that oxLDL measured directly from plasma is independently associated with subclinical carotid artery atherosclerosis in middle-aged men.

Active living and injury risk.

The purpose of this study was to get reliable insight into injury risk in various commuting and lifestyle activities, as well as recreational and competitive sports. A cohort of 3 657 persons was randomly selected from the 15- to 74-year-old Finnish population. Ninety-two percent (n = 3 363) of the subjects accepted to participate the one-year follow-up, record all their physical activities that lasted 15 min or more, and register all acute and overuse injuries that occurred during these activities. To collect the information, the study subjects were interviewed by phone by the trained personnel of the Statistics Finland three times in four-month intervals. The individual injury risk per exposure time was relatively low, ranging from 0.19 to 1.5 per 1 000 hours of participation, in commuting and lifestyle activities including walking and cycling to work, gardening, home repair, hunting and fishing, and, in sports such as golf, dancing, swimming, walking, and rowing. The risk was clearly higher in squash, orienteering, and contact and team sports, such as judo, wrestling, karate, rinkball, floorball, basketball, soccer, ice hockey, volleyball, and Finnish baseball ranging from 6.6 to 18.3 per 1 000 hours of participation. However, the highest absolute number of injuries occurred in low-risk activities, such as gardening, walking, home-repair, and cycling, because they are performed so often. In conclusion, individual injury risk per exposure hours is relatively low in commuting and lifestyle activities compared to many recreational and competitive sports. However, at a population level, these low-to-moderate intensity activities are widely practised producing a rather high absolute number of injuries, and thus, preventive efforts are needed in these activities, too.

Former exercisers of an 18-month intervention display residual aBMD benefits compared with control women 3.5 years post-intervention: a follow-up of a randomized controlled high-impact trial.

Exercise is recommended to enhance bone health but data on the maintenance of the exercise-induced bone benefit is sparse. The purpose of the study was to assess the maintenance of the musculoskeletal benefits obtained in an 18-month intervention of high-impact exercise in premenopausal women (34 former trainees and 31 controls). Physical performance and areal bone mineral density (aBMD, g/cm2) were measured at baseline, after 18 months, and after 5 years. All significant 18-month improvements relative to controls in the trainees' neuromuscular performance (isometric leg press, and vertical jump with and without additional 10% weight of the body mass) had been lost at the 5-year follow-up. However, since the changes in aBMD in both former trainees and controls by time were similar, the exercise-induced aBMD gain (i.e. the mean statistically significant intergroup differences of 1-3% in favor of the trainees) was maintained at the femoral neck, distal femur, patella, proximal tibia, and calcaneus at the 5-year follow-up. At lumbar spine, the difference was 1.7% at both 18-month and at the 5-year follow-ups but the difference was not statistically significant (NS) in the latter follow-up. At the trochanter and unloaded distal radius, the intergroup aBMD differences were NS at both the 18-month and 5-year follow-ups. In conclusion, the bone sites aBMD increased in response to the 18-month intervention, also demonstrated maintenance of this gain 3.5 years after the intervention. In contrast, the exercise-induced improvements in the neuromuscular performance vanished during the post intervention follow-up. These findings suggest the possibility of long-term bone benefits of high-impact training in women.

Walking trials in postmenopausal women: effect of low doses of exercise and exercise fractionization on coronary risk factors.

We studied the fractionization of walking training and searched for the minimum dose to affect coronary risk factors in two randomized controlled trials. Altogether 134 (Study I) and 121 (Study II) healthy, sedentary postmenopausal women started the trials, and 130 (Study I) and 116 (Study II) completed them. In Study I the exercise intensity was 65% of the maximal aerobic power (VO2max) and a total of 300 kcal was expended in one (Group W1) or two (Group W2) daily walking bouts. In Study II the exercise was continuous, and the exercise intensity (% of VO2max) and energy expenditure (kcal session(-1)) were 55% and 300 kcal (Group W3), 45% and 300 kcal (Group W4), 55% and 200 kcal (Group W5) and 45% and 200 kcal (Group W6). All the subjects walked 5 days a week. The outcome measures were blood pressure, serum lipoproteins and blood glucose and plasma insulin in fasting state and also during 2-h oral glucose tolerance test in Study I. There was no change in diastolic pressure in the original study groups, but in the combined exercise group (W1+W2) in Study I, the mean diastolic pressure declined by -3.0 mmHg (95% con-fidence interval (CI) -5.5 to -0.4) (P=0.025) in comparison with that of the controls. The mean blood glucose declined by -0.21 mmol L(-1) (CI -0.33 to -0.09) in Group W1 and -0.13 mmol L(-1) (CI -0.25 to -0.01) in Group W2 compared to controls (P=0.03). Also the 2-h glucose concentration decreased in Groups W1 and W2 compared to controls. Systolic blood pressure, serum lipoproteins and insulin levels did not change in Study I or Study II. We conclude that our training program with the greatest exercise dose, exercise intensity 65% of VO2max and weekly expenditure of 1500 kcal had a minimal, positive effect on diastolic pressure and blood glucose, and the effect was similar in one or two daily exercise session groups. This exercise dose is probably close to the minimum to affect coronary risk factors in healthy postmenopausal women. To get a more pronounced and clinically relevant effect, a greater exercise dose is needed.

Effect of alendronate and exercise on bone and physical performance of postmenopausal women: a randomized controlled trial.

In this randomized, double-blind, placebo-controlled 12-month trial we evaluated effects of weight- bearing jumping exercise and oral alendronate, alone or in combination, on the mass and structure of bone, risk factors for falling (muscle strength and power, postural sway, and dynamic balance), and cardiorespiratory fitness in postmenopausal women. A total of 164 healthy, sedentary, early postmenopausal women were randomly assigned to one of four experimental groups: (1) 5 mg of alendronate daily plus progressive jumping exercise, (2) 5 mg alendronate, (3) placebo plus progressive jumping exercise, or (4) placebo. The primary endpoint was 12-month change in bone mass and geometry (measured with dual-energy X-ray absorptiometry and peripheral computed tomography at several axial and limb sites) and physical performance; the secondary endpoint was change in biochemical markers of bone turnover. The jumping exercise was conducted an average 1.6 +/- 0.9 (mean +/- SD) times a week. Alendronate daily was effective in increasing bone mass at the lumbar spine (alendronate vs placebo 3.5%; 95% CI, 2.2-4.9%) and femoral neck (1.3%; 95% CI, 0.2-2.4%) but did not affect other bone sites. Exercise alone had no effect on bone mass at the lumbar spine or femoral neck; it had neither an additive nor an interactive effect with alendronate at these bone sites. However, at the distal tibia the mean increase of 3.6% (0.3-7.1%) in the section modulus (that is, bone strength) and 3.7% (0.1-7.3%) increase in the ratio of cortical bone to total bone area were statistically significant in the exercise group compared to the nonexercise group, indicating exercise-induced thickening of the bone cortex. Bone turnover was reduced in alendronate groups only. Alendronate had no effect on physical performance while the jumping exercise improved leg extensor power, dynamic balance, and cardiorespiratory fitness. As conclusion Alendronate is effective in increasing bone mass at the lumbar spine and femoral neck, while exercise is effective in increasing the mechanical properties of bone at some of the most loaded bone sites, as well as improving the participants' muscular performance and dynamic balance. Together alendronate and exercise may effectively decrease the risk of osteoporotic fractures.

Associations of hormone replacement therapy with bone structure and physical performance among postmenopausal women.

The purpose of this cohort study was to focus on factors associated with bone mass and structure of lower limbs and physical performance after menopause. Eighty nonsmoking women with a mean age of 62.1 (SD 0.8) years participated in the study. They were classified into two groups by their use of hormone replacement therapy (HRT), either the current users (n = 43) or the never or discontinued users (n = 37). The tibial shaft and distal tibia were scanned with peripheral computed tomography. For the shaft region, the bone mineral content (BMC, g), cortical density (CoD, g/cm(3)), cortical area (CoA, mm(2)), and section modulus (BSI, mm(3)) were determined. For the distal part, the evaluated variables were BMC, total area (ToA), ratio of cortical to total area (CoA/ToA), trabecular density (TrD, g/mm(3)), cortical thickness, BSI, and buckling ratio. Isometric and dynamic muscle strength of the leg extensors, agility and postural sway, and cardiorespiratory capacity (VO(2max)) were measured. Unadjusted values for all bone variables were slightly higher among the HRT users compared to nonusers, with the exception of TrD with no difference. After controlling for body weight, the mean differences (95% confidence interval) remained significant for CoD of the tibial shaft and BSI of the distal tibia, the mean between-group differences being 1.5% (0.4 to 2.5%) and 23.0% (7.1 to 41.3%), respectively. Underlying the greater bending strength, HRT users had thicker cortices and a greater ratio of CoA/ToA. No differences existed between the two study groups for lower limb isometric or dynamic power, cardiorespiratory capacity, or postural balance or sway. HRT may offer protection against bone loss and maintain bone strength, although its ability to improve physical performance is not evident.

Improved functional status in 16 years of follow up of middle aged and elderly men and women in north eastern Finland.

STUDY OBJECTIVE: To investigate age, period, and cohort effects on functional status. DESIGN: A prospective cohort study with measurements in 1981, 1990, and 1996. SETTING: Three municipalities in north east Finland. PARTICIPANTS: A regionally representative sample of 19 to 63 year old men and women was drawn from the census data in 1979, of which 758 men and 1033 women initially aged 39-63 years entered the study in 1980 and completed the follow up in 1996 (90.9% of the alive cohort). MEASUREMENTS AND MAIN RESULTS: Functional status was determined based on self estimated disabilities (difficulties or not able) to walk 2 km, climb several flights of stairs, and run 100 m. The age adjusted odds of disability in stair climbing and running were lower among the men and the women in 1990 and 1996 than among the men and the women in 1981. There was a declining trend in the odds of disability with succeeding birth cohorts among both the men (odds ratios (OR) 0.79 and 95% confidence intervals (CI) 0.70 to 0.88 for stair climbing and OR 0.88 and 95% CI 0.78 to 0.98 for running) and the women (OR 0.85 and 95% CI 0.77 to 0.93 for stair climbing and OR 0.85 and 95% CI 0.76 to 0.94 for running). No statistically significant differences in walking disability were found between the study periods or the study cohorts. CONCLUSIONS: The findings depict an improved time trend in functional status in the study population, with implications for future health and social care planning.

Does previous participation in high-impact training result in residual bone gain in growing girls? One year follow-up of a 9-month jumping intervention.

The skeletal response to exercise and training on bone is exceptionally good during the growing years. However, it is not known whether the benefit of training on bone is maintained after the training. This 20-month follow-up study assessed the effect of a 9-month jumping intervention on bone gain and physical performance in 99 girls (mean age 12.5 +/- 1.5 years at the beginning of the study) one year after the end of the intervention. Both bone mineral content (BMC), by dual energy X-ray absorptiometry (DXA) at the lumbar spine and proximal femur, and physical performance parameters (standing long jump, leg extension strength, and shuttle run tests) were measured at baseline and at 20 months. A multivariate regression analysis was first used to determine the best predictors of the BMC accrual by time. Analysis showed that age at baseline and square of age, changes in height and weight, and pubertal development into Tanner stages 4 and 5 during the follow-up explained the majority of the BMC gain. Then, the effect of participation in the 9-month exercise intervention on BMC accrual and physical performance was analysed adding this variable (participation: yes/no) into the model. The regression analysis showed that the trainees (N = 50) had 4.9 % (95 % CI, 0.9 % to 8.8 %, p = 0.017) greater BMC increase in the lumbar spine than the controls (N = 49). The mean 20-month BMC increase in the lumbar spine was 28 % (SD 19) in the trainees compared to 22 % (12) increase in the controls. In the proximal femur, the trend was similar but the obtained 2 to 3 % higher BMC accrual in the trainees (compared to that in controls) were statistically insignificant. Among the performance variables, using the same model that best predicted the BMC accrual, the only statistically significant between-groups difference, in favour of the trainees, was the improvement in the standing long jump test (6.4 %, 95 % CI, 2.3 % to 10.4 %, p = 0.002). Improvements in the leg extension strength and shuttle run tests showed no between-groups difference. In conclusion, although the greatest proportion of bone mineral accrual in growing girls is attributable to growth, an additional bone gain achieved by jumping training is maintained at the lumbar spine at least a year after the end of the training.

Walking trials in postmenopausal women: effect of one vs two daily bouts on aerobic fitness.

We compared the effects of one vs two daily bouts of walking on aerobic fitness and body composition in postmenopausal women. One hundred and thirty-four subjects were randomized into exercise groups or a control group and 130 completed the study. The subjects walked 5 d/week for 15 weeks at 65% of their maximal aerobic power expending 300 kcal (1255 kJ) in exercise in one (Group S1) or two daily sessions (Group S2). VO(2max) was measured in a direct maximal treadmill test. Body mass index (BMI) was calculated and the percentage of body fat (fat%) estimated using skinfold measurements. The net change in the VO(2max) was 2.5 mL min/kg (95% CI 1.5, 3.5) (8.7%) in Group S1 and 2.5 mL min/kg (95% CI 1.5, 3.5) (8.8%) in Group S2. The net change in body mass was -1.2 kg (95% CI-1.9, -0.5) in Group S1 and -1.1 kg (95% CI -1.8, -0.4) in Group S2. The net fat% change was -2.1% (95% CI-2.7, -1.4) in Group S1 and -1.7% (95% CI-2.3, -1.0) in Group S2. Exercise improved the maximal aerobic power and body composition equally when walking was performed in one or two daily bouts.

Randomised, controlled walking trials in postmenopausal women: the minimum dose to improve aerobic fitness?

BACKGROUND: The American College of Sports Medicine recommends 20-60 minutes of aerobic exercise three to five days a week at an intensity of 40/50-85% of maximal aerobic power (VO(2)MAX) reserve, expending a total of 700-2000 kcal (2.93-8.36 MJ) a week to improve aerobic power and body composition. OBJECTIVE: To ascertain the minimum effective dose of exercise. METHODS: Voluntary, healthy, non-obese, sedentary, postmenopausal women (n = 121), 48-63 years of age, were randomised to four low dose walking groups or a control group; 116 subjects completed the study. The exercise groups walked five days a week for 24 weeks with the following intensity (% of VO(2)MAX) and energy expenditure (kcal/week): group W1, 55%/1500 kcal; group W2, 45%/1500 kcal; group W3, 55%/1000 kcal; group W4, 45%/1000 kcal. VO(2)MAX was measured in a direct maximal treadmill test. Submaximal aerobic fitness was estimated as heart rates at submaximal work levels corresponding to 65% and 75% of the baseline VO(2)MAX. The body mass index (BMI) was calculated and percentage of body fat (F%) estimated from skinfolds. RESULTS: The net change (the differences between changes in each exercise group and the control group) in VO(2)MAX was 2.9 ml/min/kg (95% confidence interval (CI) 1.5 to 4.2) in group W1, 2.6 ml/min/kg (95% CI 1.3 to 4.0) in group W2, 2.4 ml/min/kg (95% CI 0.9 to 3.8) in group W3, and 2.2 ml/min/kg (95% CI 0.8 to 3.5) in group W4. The heart rates in standard submaximal work decreased 4 to 8 beats/min in all the groups. There was no change in BMI, but the F% decreased by about 1% unit in all the groups. CONCLUSIONS: Walking (for 24 weeks) at moderate intensity 45% to 55% of VO(2)MAX, with a total weekly energy expenditure of 1000-1500 kcal, improves VO(2)MAX and body composition of previously sedentary, non-obese, postmenopausal women. This dose of exercise apparently approaches the minimum effective dose.

Association of physical activity and calcium intake with the maintenance of bone mass in premenopausal women.

Altogether 92 initially 25- to 30-year-old women of 132 original subjects participated in this 4-year follow-up study, which evaluated the influence of physical activity and calcium intake on the bone mineral content (BMC) of premenopausal women. The subjects were originally selected for a cross-sectional study according to their level of physical activity (high PA+ and low PA-) and calcium intake (high Ca+ and low Ca-), and the original groups were maintained in this follow-up study. The mean loss of BMC (95% CI) in the pooled data was 1.5% (0.7% to 2.4%) at the femoral neck, 0.6% (-0.8% to 1.9%) at the trochanter and 6.0% (4.5% to 7.4%) at the distal radius during the 4-year follow-up. According to repeated measures analyses of covariance neither physical activity nor physical fitness at baseline was associated with the rate of bone loss from the proximal femur. High calcium intake and the maintenance of body weight were both associated with a lower rate of bone loss from the proximal femur and distal radius. In addition, a long duration of breast feeding was associated with a higher rate of bone loss from the distal radius.

Site-specific skeletal response to long-term weight training seems to be attributable to principal loading modality: a pQCT study of female weightlifters.

Physical training may be able to improve bone strength through site-specific changes in the composition, size and structure of the bone without notable increases in volumetric density. To address this possibility specifically, we compared 14 competitive female weightlifters with 14 female physical therapy students. Peripheral quantitative computed tomographic scans (pQCT) were taken from the distal radius, radial shaft, distal femur, and tibial midshaft of the dominant limb. Analysis of covariance (ANCOVA) was used to estimate the intergroup differences, using body weight and age as covariates. Cortical density did not differ between the weightlifters and controls at any site, whereas trabecular density was greater in the weightlifters, the benefit being 10% (P = 0.186) at the distal radius and 11% (P = 0.040) at the distal femur compared with the controls. Weightlifters' cortical cross-sectional area was 38% (P = 0.029) larger at the distal radius, 26% larger (P = 0.001) at the radial shaft, and 9% larger at the tibial midshaft (P = 0.034). Consequently, the weightlifters' forearm bone strength indices were also significantly higher, the intergroup difference being 41% (P = 0.001) at the distal radius and 43% (P = 0.004) at the radial shaft. Thus, the observed intergroup difference at the distal radius was mainly due to enlarged bone, particularly its cortex, rather than higher volumetric bone density. Findings at the radial shaft were similar. In contrast, weightlifters' trabecular tissue at the distal femur was denser but the bone per se was not clearly bigger than that of the controls' (intergroup difference 5%, P = 0.117). We suggest that bones subjected to exceptionally high bending-loading (distal radius and radial shaft) are larger than their normal counterparts while at sites experiencing axial, compressive-loading (e.g., distal femur), a denser trabecular structure (more load-carrying area) may be sufficient and any substantial enlargement in bone size may not be necessary.

Continuously rising problem of osteoporotic knee fractures in elderly women: nationwide statistics in Finland in 1970-1999 and predictions until the year 2030.

We assessed the current trends in the number and incidence of osteoporotic knee fractures in Finland by collecting data from the National Hospital Discharge Register for all patients > or =60 years of age who were admitted to Finnish hospitals in 1970-1999 for primary treatment of such fractures. The knee fracture was defined "osteoporotic" if it was caused by a low-energy trauma only; that is, a fall from standing height or less. We also predicted fracture development until the year 2030 by a regression model, which took into account the predicted changes in the fracture incidences and population at risk. The number and incidence (per 100,000 persons) of osteoporotic knee fractures in Finnish women aged > or =60 years clearly rose during the study period, from 218 (number) and 55 (incidence) in 1970 to 685 and 113 in 1999. Even after age adjustment, the incidence of women's fractures showed a clear increase, from 59 in 1970 to 105 in 1999. If this trend continues, there will be about 2.5 times more osteoporotic knee fractures in Finnish women in the year 2030 than there were in 1999. In Finnish men aged > or =60 years, the annual number of fractures and its changes were clearly smaller (77 in 1970 vs. 138 in 1999), and the fracture incidence did not show consistent trend changes over time (30 in 1970 vs. 34 in 1999). We conclude that in elderly Finnish women the number of osteoporotic knee fractures shows a rise with a rate that cannot be explained merely by demographic changes and, therefore, vigorous preventive measures are needed to control this development.

Health benefits of physical activity with special reference to interaction with diet.

Regular physical activity causes numerous and substantial performance-improving and health-enhancing effects. Most of them are highly predictable, dose-dependent and generalizable to a wide range of population groups. Many of the biological effects of regular, moderate physical activity translate into substantially reduced risk of coronary heart disease, cerebrovascular disease, hypertension, maturity onset diabetes, overweight and obesity, and osteoporosis. These effects also substantially reduce the risk of deterioration of functional capacity. In the genesis of these conditions, a lack of physical activity and inadequate nutrition act synergistically and in part additively, and they operate largely through the same pathways. It is conceivable to suggest that the prevalence of, e.g, the above mentioned metabolic diseases is so high in Europe largely because of the high prevalence of sedentariness and inadequate nutrition. Thus, both physical activity and nutrition have to be given strong emphasis in policies, strategies and programmes that will be developed and implemented for improving the health of Europeans.

Sports injuries in floorball: a prospective one-year follow-up study.

Two hundred and ninety-five licensed floorball players from Finnish premier to fifth division were observed prospectively for one season to study the incidence, nature, causes and severity of floorball injuries. During the study period, 100 out of the 295 (34 %) players sustained 120 injuries. Thirty-seven percent (73/199) of the male players and 28 % (27/96) of the females suffered from an injury. The injury rate was 1.0 per 1000 practice hours for both sexes. The injury rates per 1000 game hours were 23.7 for men and 15.9 for women. One hundred injuries (83 %) were acute and the remaining 20 (17 %) were overuse injuries. Sprain was the most common type of injury in men while overuse injuries were the most frequent injury type in women. The lower extremity was involved in 62 %, spine or trunk in 19 % and upper extremity in 10 % of the injuries. The most commonly injured sites were the knee and ankle (22 % and 20 % of all injuries), followed by head and neck (8 %). In both sexes the majority of injuries were minor, level II, injuries. Ten of the knee injuries (38 %) were serious, level IV injuries, of which seven were ACL ruptures. In conclusion, the individual risk of injury in floorball is relatively low in game practice while rather high during the game itself. Before initiation of clinical trials on prevention of floorball injuries, an exact knowledge of the risk factors and mechanisms of floorball injuries are needed.

Relationship between high-density lipoprotein paraoxonase gene M/L55 polymorphism and carotid atherosclerosis differs in smoking and nonsmoking men.

The enzyme paraoxonase (PON) can eliminate lipid peroxides and is believed to protect against low-density lipoprotein oxidation. A common polymorphism in the PON gene (PON1) causes an amino acid substitution of methionine (M) for leucine (L) at position 55 in the protein, which changes the activity of PON and can affect the risk of atherosclerosis. Because smoking is associated with increased lipid peroxidation, we studied the relationship between PON M/L55 polymorphism and the carotid artery intima-media thickness (IMT) in smokers or previous smokers (n = 112) and nonsmokers (n = 87). IMT was measured at 3 standardized segments by B-mode ultrasonography, and the overall mean IMT value of 199 randomly selected men (mean age 54.2 +/- 3.0 years) was calculated. Subjects with IMT > 1.7 mm in at least 1 standard site were considered to have carotid artery atherosclerotic disease (CAAD). For analysis, L55 homozygotes were compared with the M55 allele carriers. Nonsmoking L55 homozygotes had an 8.9% (95% confidence interval [CI], 1.6 to 16.8) higher overall mean IMT than M55 allele carriers. In smokers, however, the M55 allele carriers tended to have higher overall mean IMT values than L55 homozygotes. There was also a statistically significant interaction between M/L55 genotype and smoking status on CAAD (P =.009) by logistic regression analysis. Among nonsmokers, the L55 homozygotes had an odds ratio of 4.22 (95% CI, 1.06 to 16.8) for CAAD compared with nonsmoking M55 allele carriers. Contrary to nonsmokers, the smoking M55 allele carriers had an odds ratio of 2.22 (95% CI, 0.82 to 6.01) for CAAD when the L55/L55 genotype of smokers was a reference group. These data suggest that in nonsmoking men, a PON L55/L55 genotype may represent a genetic risk factor for CAAD. The reverse effect in smokers implies that the ability of PON to protect against CAAD is influenced by cigarette smoking. The efficiency of this inhibition probably depends on the PON M/L55 genotype.

Bone mineral density of visually handicapped women.

While physical activity is an essential factor for muscle performance and development and also for the maintenance of bone mass in the loaded bones, apparently low intensity of physical activity of blind persons may compromise the muscle performance and bone mineral density (BMD). Therefore, the aim was to study whether there are differences in BMD of the weight-bearing or non-weight-bearing bones between visually handicapped persons and those with normal sight. Nineteen visually handicapped premenopausal women and their matched pairs were recruited to the study. The mean age of the visually handicapped women was 39.9 years (SD 8.1) and that of the women with normal vision 39.7 years (6.5). BMD of the distal radius, femoral neck and trochanter was measured with dual energy X-ray absorptiometry (DXA), and isometric muscle strength of the extremities and trunk with a dynamometer. Between-group differences were compared with paired Student's t-test. The BMD at the femur was 8% higher in favour of the group with normal sight, whereas radial BMD was similar in the two groups. The t-score was -1.0 (95% confidence interval -1.5 to -0.5) for the femoral neck BMD and -0.7 (-1.1 to -0.2) for the trochanter BMD in the group with impaired vision. The respective t-scores for the group with normal sight were -0.3 (-0.9 to 0.3) for the femoral neck and 0 (-0.7 to 0.7) for the trochanter. Visual handicap seems to be a risk for lower BMD of the weight-bearing proximal femur, but not for lower BMD of the non-weight-bearing distal radius.

Maintenance of body weight, physical activity and calcium intake helps preserve bone mass in elderly women.

This prospective study focused on lifestyle factors and weight maintenance that may modulate the rate of bone loss at the weight-bearing proximal femur and non-weight-bearing distal radius in elderly women. Altogether 128 women of 134 subjects participated in this study with a mean follow-up time 3.9 years (range 2.9-5.3 years). The initially 60- to 65-year-old subjects were originally selected by their level of physical activity [high (PA+) and low (PA-)] and calcium intake [high (Ca+) and low (Ca-)], and the original groups were maintained in this study. Physical fitness and bone mineral content (BMC) decreased significantly at a similar rate in all four study groups without any statistically significant between-group difference. The mean change in the muscle strength of leg extensors was -3.3% (95% CI -5% to -1.5%) at follow-up when including all individuals. The leg extension strength was still 9.2% (95% CI 2.7% to 16.1%) better in the PA+ groups compared with PA- groups at follow-up. The mean change in the forearm flexion strength was -14% (95% CI -16.5% to -11.3%) at follow-up with no difference in the strength level between PA+ and PA- groups. The mean change in the estimated oxygen uptake was -3.4% (95% CI -5.6% to -1.1%) at follow-up. The PA+ groups were still fitter, the between-group difference in the estimated oxygen uptake being 11.9% (95% CI 4.8% to 19.5%). The mean changes in BMC at follow-up were -2.1% (95% CI -3.0% to -1.2%) at the femoral neck, -1.9% (95% CI -3.2% to -0.5%) at the trochanter, and -12.4% (95% CI -15.4% to -9.4%) at the distal radius, indicating mean annual losses of 0.6% (95% CI 0.3% to 0.8%), 0.5% (95% CI 0.1% to 0.8%), and 3.2% (95% CI 2.4% to 4.0%), respectively. Decreased body weight was associated with higher bone loss in all measured bone sites. High calcium intake and better preservation of physical fitness were associated with a smaller decrease in femoral neck BMC.