Dairy product consumption, eating habits, sedentary behaviour and physical activity association with bone mineral density among adolescent boys: a cross-sectional observational study.

BACKGROUND: During childhood and adolescence, skeletal microarchitecture and bone mineral density (BMD) undergo significant changes. Peak bone mass is built and its level significantly affects the condition of bones in later years of life. Understanding the modifiable factors that improve bone parameters at an early age is necessary to early prevent osteoporosis. To identify these modifiable factors we analysed the relationship between dairy product consumption, eating habits, sedentary behaviour, and level of physical activity with BMD in 115 young boys (14-17 years). METHODS: Bone parameters were measured by dual energy x-ray absorptiometry using paediatric specific software to compile the data. Dairy product consumption and eating habits were assessed by means of a dietary interview. Sedentary behaviour and physical activity was assessed in a face-to-face interview conducted using the International Physical Activity Questionnaire. Data collection on total physical activity level was performed by collecting information on the number of days and the duration of vigorous and moderate intensity (MVPA) and average daily time spent in sitting (SIT time). RESULTS: The strongest relationships with BMD in distal part of forearm were found for moderate plus vigorous activity, sit time, and intake of dairy products, intake of calcium, protein, vitamin D, phosphorus from diet. Relationships between BMD, bone mineral content (BMC) in the distal and proximal part of the forearm and PA, sit time and eating parameters were evaluated using the multiple forward stepwise regression. The presented model explained 48-67% (adjusted R2 = 0.48-0.67; p < 0.001) of the variance in bone parameters. The predictor of interactions of three variables: protein intake (g/person/day), vitamin D intake (µg/day) and phosphorus intake (mg/day) was significant for BMD dis (adjusted R2 = 0.59; p < 0.001). The predictor of interactions of two variables: SIT time (h/day) and dairy products (n/day) was significant for BMD prox (adjusted R2 = 0.48; p < 0.001). Furthermore, the predictor of interactions dairy products (n/day), protein intake (g/person/day) and phosphorus intake (mg/day) was significant for BMC prox and dis (adjusted R2 = 0.63-0.67; p < 0.001). CONCLUSIONS: High physical activity and optimal eating habits especially adequate intake of important dietary components for bone health such as calcium, protein, vitamin D and phosphorus affect the mineralization of forearm bones.

Relation between skin temperature and muscle stiffness in masters athletes: Effect of specific training adaptation.

Aging process is correlated with negative changes in muscles properties such as their thermal responsiveness and stiffness. At the same time masters athletes are often considered as an exemplars of successful aging. Taking this into account, the aim of the study was to establish thermal portrait of lower limbs in Masters Athletes in Track & Field competing in 200 m race as well as to find out the effect of exercise on muscle stiffness. Thermal images and myotonometry were applied at restin state and immediately after the race. Indoor sprint in Masters athletes did not cause significant skin temperature changes. Only assymetries were found for Biceps femoris muscle (left vs right before p = 0,0410; after p = 0,046). Gastrocnemius was the most responsive area for sprinting in terms of muscle stiffness. Some specific adaptations to sprint were found. Masters athlete's thermal profile of lower extremities was generally characterized by symmetry. Maximal exertion did not result in an increase in muscle stiffness among the athletes, suggesting the positive influence of sports training in aging athletes.

Forearm bone mineral density in adult men after spinal cord injuries: impact of physical activity level, smoking status, body composition, and muscle strength.

BACKGROUND: In the present cross-sectional study, we analyzed the relationships of physical activity level, muscle strength, body composition, injury parameters, and smoking status with bone health in the non-paralyzed upper limb in adult men after spinal cord injuries (SCI). METHODS: The study covered 50 men after spinal cord injuries aged 35.6 ± 4.9 years (25 wheelchair rugby players and 25 non-athletes). Forearm bone mineral density (BMD), bone mineral content (BMC) in distal (dis) and proximal (prox) part was measured by densitometry. Body mass index (BMI) and body fat percentage (BF) were calculated. Fat mass (FM) and fat-free mass (FFM) were estimated from somatic data. An interview was conducted based on the Global Adult Tobacco Survey questionnaire. Muscle strength (maximal hand grip strength) was measured using a Jamar dynamometer. RESULTS: Active male smokers after SCI had significantly lower BMD dis, BMC dis and prox, T-score dis, and prox (large effect > 0.8) than male non-smokers after SCI. Physical activity was a significant predictor (positive direction) for BMC prox (adjusted R2 = 0.56; p < 0.001). The predictor of interactions of physical activity and fat mass was significant for BMC dis (positive direction, adjusted R2 = 0.58; p < 0.001). It was also found that the predictor of interactions of four variables: physical activity, fat mass, hand grip strength (positive direction), and years of active smoking (negative direction) was significant for BMD dis (adjusted R2 = 0.58; p < 0.001). The predictor of interactions of age at injury (additive direction) and the number of cigarettes smoked per day (negative direction) was significant for T-score prox (adjusted R2 = 0.43; p < 0.001). Non-smoking physically active men after SCI had the most advantageous values of mean forearm BMD. CONCLUSION: Rugby can be considered a sport that has a beneficial effect on forearm BMD. The physically active men after SCI had significantly higher bone parameters. Physical activity itself and in interactions with fat mass, hand grip strength (positive direction), and years of active smoking (negative direction) had a significant effect on bone health in non-paralyzed upper limbs. Active smoking may reduce the protective role of physical activity for bone health.

Autoimmune sclerosing cholangitis might be triggered by SARS-CoV-2 infection in a child - a case report.

The spectrum of liver involvement during coronavirus disease 2019 (COVID-19) is broad and mainly includes elevated liver enzymes and cholestasis. Severe acute respiratory syndrome corona- virus-2 (SARS-CoV-2) infection most often leads to a transient moderate increase in liver enzymes that is not accompanied by disturbances in the synthetic function of the liver. However, there is increasing evidence that SARS-CoV-2 infection is associated with the development of autoimmune disorders. The pathogenesis of autoimmune hepatobiliary diseases is not fully understood, taking into account genetic and environmental factors such as viral infections. We present a pediatric case of autoimmune sclerosing cholangitis (ASC), which was diagnosed 2 months after SARS-CoV-2 infection. To the best of our knowledge, ASC potentially triggered by COVID-19 has not been reported in pediatric patients. Further studies are needed to describe the clinical impact of the development of autoimmune liver diseases potentially associated with SARS-CoV-2 infection in pediatric patients. Our observations indicate that children with liver injury potentially caused by COVID-19 require long-term monitoring of liver function parameters.

Assessment of intake of calcium and vitamin D and sun exposure in the context of osteoporosis risk in a study conducted on perimenopausal women.

INTRODUCTION: The results of many epidemiological and clinical studies have shown that osteoporosis is a multifactorial disease and develops mainly in women during menopause. The aim of this study was to evaluate the diet with particular emphasis on calcium and vitamin D intake and sun exposure in premenopausal women in terms of risk of osteoporosis. MATERIAL AND METHODS: The study involved 300 women aged 45-55 years from Warsaw. The method used was a questionnaire assessing the frequency of consumption from the last three months. Exposure to the sun evaluated using a questionnaire prepared in cooperation with the Institute of Food and Nutrition in Warsaw. For the purpose of the project, profiles of attitudes towards prevention of osteoporosis were developed. RESULTS: Inadequate intake of calcium and vitamin D among the majority of women surveyed was confirmed. The highest percentage of women represented profile VIII: attitudes towards prevention of osteoporosis, characterized by insufficient exposure to sunlight and a diet deficient in both calcium and vitamin D. CONCLUSIONS: In the diets of women surveyed significant deficiencies of calcium and vitamin D were found, which confirms previous reports on the lack of nutritional support for normal women's bone mineralization. Among the surveyed women the majority reported insufficient exposure to sunlight as a source of vitamin D additional to food. There is a need for health education of these women in the prevention of osteoporosis and especially paying attention to the proper intake of calcium and more vitamin D in their diet. At the same time, adequate exposure to the sun is vital as it is the main source of vitamin D for the body coming not from the food consumed.

Recovery effect of self-myofascial release treatment using different type of a foam rollers.

Among athletes, foam rolling is popular technique of myofascial release aimed to support recovery processes and counteract delayed onset muscle soreness. However, there is no consensus on the optimal parameters of the roller texture used in the procedure. The study aimed to determine whether using rollers with different textures and hardness (smooth/soft, grooved/mid, serrated/hard) in myofascial release affects post-exertional restitution rate and the level of perceived DOMS (Delayed Onset Muscle Soreness) after intense anaerobic exercise. The study involved 60 healthy and physically active men randomly divided into three experimental groups and one control group (passive rest)-each consisting of 15 individuals: STH-rolling with a smooth roller; G-rolling with a grooved roller; TP-rolling with a serrated roller; Pass-passive rest group. After performing a exercise test (one-minute high-intensity squat), blood lactate (LA), creatine kinase (CK) and pain perception (VAS Scale) were monitored. The analysis of the average LA concentration in the blood 30 min post-exercise showed a statistical difference for all rolling groups compared to the passive rest group: STH (p < 0.001), G (p < 0.001), TP (p = 0.035). No statistically significant differences were found between the CK measurement results in individual assessments. Statistically significant differences in VAS values were observed between G (p = 0.013) and TP (p = 0.006) groups and the Pass group at 48 h, as well as between STH (p = 0.003); G (p = 0.001); TP (p < 0.001) groups and the Pass group at 72 h. Based on statistical data, a strong influence (η2 = 0.578) of time on the quadriceps VAS variable was noted. The research results confirm the effectiveness of rolling in supporting immediate and prolonged recovery. The conducted studies indicate a significantly better pace of post-exertional recovery after a rolling procedure lasting at least 120 s. The texture and hardness of the tool used did not matter with such a duration of the treatment.

Determinants of bone mineral density in various regions of the skeleton among smokers and non-smokers: the role of physical activity.

Background: The adult human skeleton is composed of cortical and cancellous bone. The proportions of these two types of bone tissue differ in various parts of the skeleton. The aim of this cross-sectional study was to quantify the determinants of bone mineral density (BMD) and bone mineral content in various regions of interest (ROIs) in smokers and never-smokers. Methods: In this study, 4,332 bone scans of three regions of interest (ROIs) were analyzed: the forearm (distal and proximal), femur, and lumbar spine. Body composition and bone parameters were measured using dual-energy X-ray absorptiometry. Smoking was measured using the Global Adult Tobacco Survey questionnaire. Body mass index (BMI) was calculated, and physical activity (PA) was characterized by the metabolic equivalent of task (MET). Results: Among women, the interaction between PA (positive ß coefficient) and smoking (negative ß coefficient) was a significant predictor of BMD in the distal and proximal forearm (adj. R2 = 0.40 and R2 = 0.58; p < 0.001). The interaction of three variables-age, smoking (negative ß), and MET (positive ß)-was significant for total hip BMD (adj. R2 = 0.54; p < 0.001). The interaction between BMI and MET (positive ß) and smoking (negative ß) was significant for BMD in the lumbar spine (adj. R2 = 0.62; p < 0.001). In men, the interaction between MET (positive ß) and smoking (negative ß) was significant for BMD in the forearm and lumbar spine (adj. R2 = 0.44, R2 = 0.46, and R2 = 0.49; p < 0.01). Smoking alone was a significant negative predictor of total hip BMD (adj. R2 = 0.34; p < 0.001). Conclusion: Among both women and men, never-smokers had significantly better bone parameters than smokers. Smoking was a significant negative predictor for BMD in the various ROIs in both women and men. Physical activity was a significant positive predictor of BMD, with a strong association with bone parameters.

Does predicted age at peak height velocity explain physical performance in U13-15 basketball female players?

BACKGROUND: The aims of the study were (1) to identify the physical fitness and basic anthropometric characteristics of Polish female basketball players aged 13-15 years, (2) to show the effect of maturity timing on the performance in motor tests and basic body composition parameters, (3) to identify the index that contributes most to the prediction of performance in the tests of speed, jumping ability, agility, and endurance. METHODS: The sample included 904 female Polish players (U13-15). In part 1, maturity timing category distribution were examined within across age-groups. Maturity timing was followed by grouping with respect to years before or after the observed peak high velocity (PHV): PHV0 (- 0.50 to 0.49), PHV1 (0.50 to 1.49), PHV2 (1.50 to 2.49) and PHV3 (2.50 to 3.49). In part 2, the relationship between the anthropometric variables, physical fitness performance was assessed based on maturity timing categories (ANCOVA analysis). In part 3, backward stepwise multiple regression analyse quantified the relationship between maturity timing (group of PHV) and physical performance. RESULTS: ANCOVA results (age, body height, and body mass as covariates) showed in the U13 female basketball players significantly higher sprinting (20 m), jumping ability and endurance tests results of the PHV1 group. Better results was observed in U14 female players in PHV1 compared to PHV2 and PHV3 in 20 m and jumping tests but opposite trend was observed for 5 m sprint and endurance test (distance covered and VO2max). U15 basketball players from the PHV3 group were characterized by better results of jumping abilities, endurance, 10 m and 20 m sprint and agility (total, S4) tests. Maturity timing (10 m), chronological age (5 m, 20 m, agility, SVJ, VJ, and VO2max tests), body height (10 m), body mass (10 m, 20 m, VJ, VO2max), and the interaction between body mass and height (SVJ) were significant (adjusted R2 = 0.02-0.10; p < 0.001) predictors of motor skills. CONCLUSION: Trainng content of female basketball players aged 13-15 years old should be adjusted to biological requirements especially in jumping, endurance and 20 m sprint test. The time from peak height velocity (PHV) was a significant predictor only in the 10 m sprint test.

Bone mineral density and body composition in Polish girls with Myelomeningocele: effects of adapted physical activity and past fractures.

The aim of this cross-sectional study was to evaluate the relationship between the condition of bone mineral density and body composition and the adapted physical activity, the number of past fractures and selected somatic characteristics of girls with myelomeningocele (MMC). The study examined 37 girls with myelomeningocele (MMC) at the age of 11.9 ± 1.8 years. Bone mineral content (BMC) and bone mineral density (BMD) of the forearm were measured by dual-energy X-ray absorptiometry (DXA). Anthropometric measurements were also made and selected anthropological indices were calculated. A percentage of body fat, fat mass (FM in kg) and fat-free body mass (FFM in kg) were calculated, whereas the incidence of fractures of lower and upper limbs was evaluated during interviews. Underestimated BMD characteristic for osteopenia occurred only in physically inactive girls. Low % age-matched was observed in all physically inactive girls, whereas it was less pronounced in physically active girls. Statistically significant positive correlations were found between BMD and: body height, sitting height, body weight, BMI, fat mass and fat-free mass. Regardless of physical activity, significantly higher Z-score values (F = 12.9; p ≤ 0.001) were observed in girls who had not suffered from fractures compared to their peers who reported one or more past fractures in different skeletal locations. Active participation in physical activity of children with MMC may be a factor determining good bone tissue condition. The prevention of fractures in children in wheelchairs can be an important part of maintaining healthy bone tissue and a better quality of life.

Bone mineral density in elite masters athletes: the effect of body composition and long-term exercise.

BACKGROUND: The purpose of the study was to examine how bone mineral density (BMD) is related to body composition depending on the practiced sport (endurance, speed-power, throwing sports) in participants of the World Masters Athletics Championship. METHODS: Dual-energy X-ray absorptiometry (DXA) was used to determine BMD and bone mass (BMC). Body composition was analyzed by means of the JAWON Medical X-scan analyzer using bioelectrical impedance methods. Percentage body fat (%BF), body fat mass (BFM), lean body mass (LBM), total body water (TBW), soft lean mass (SLM), intracellular water (ICW), and extracellular water (ECW) were evaluated. RESULTS: Among men, the most important variables affecting the BMD norm were LBM (OR = 32.578; p = 0.023), ECW (OR = 0.003; p = 0.016) and ICW (OR = 0.011; p = 0.031), in the distal part and SLM (OR = 5.008; p = 0.020) and ICW (0.354, p = 0.008) in the proximal part. In women, the most important predictors of normal BMD were ICW (OR = 10.174; p = 0.003) and LBM (OR = 0.470; p = 0.020) in the distal part and ICW (OR = 5.254; p = 0.038) in the proximal part. CONCLUSION: The representatives of strength based events had the most advantageous BMD levels. The condition of bone tissue evaluated by BMC and BMD of the forearm in masters athletes was strongly determined by the level of lean body components and the type of sports training associated with the track and field event. In the most important predictors of the BMD norm were also hydration components ECW and ICW. However, this relationship requires more research on the nature and mechanisms of these interactions.

Determinants of bone health in adults Polish women: The influence of physical activity, nutrition, sun exposure and biological factors.

PURPOSE: The aim of this study was to assess the determinants of bone health in the group of women over 40 years old. Lifestyle factors such as past and present physical activity, past and present sun exposure, current dietary intake of calcium and vitamin D, nutritional status as measured by BMI, family history of osteoporosis and current hormonal status were analysed. METHODS: The study involved 500 women over 40 years old. All examined women was the same ethnicity- European origin. Methods used: densitometry method (DXA), bioelectrical impedance analysis, International Physical Activity Questionnaire, nutrition questionnaire, past and present sun exposure questionnaire. Past and present physical activity, past and present sun exposure and sufficient level of calcium in the diet proved to be the most important factors determining mineralization of bone tissue of women. In order to indicate an independent association of the correct bone tissue mineralization with individual factors, multivariate analysis was used-logistic regression. RESULTS: The norm BMD in the distal part of the forearm was strongly influenced: recommended dietary calcium intake (OR = 5.95; p = 0.003), moderately (OR = 1.88; p = 0.053) and high (OR = 14.0; p<0.001) past physical activity, sufficient (OR = 4.97; p<0.001) and high (OR = 18.9; p = 0.004) level of present physical activity, sufficient past (OR = 5.15; p<0.001) and sufficient present sun exposure (OR = 10.0; p<0.001). The chance for the BMD prox norm was also increased several times: high past physical activity (OR = 68.4; p<0.0001) and sufficient past sun exposure (OR = 10.6; p<0.001), moderate past activity (OR = 4.20; p<0.001), sufficient (OR = 6.13; p<0.001) and high (OR = 10.0; p<0.001) present physical activity, sufficient present sun exposure (OR = 9.09; p<0.0001), recommended intake of calcium (OR = 9.57; p<0.001) and vitamin D (OR = 2.68; p = 0.052). Whereas e significantly lower likelihood for the BMD prox norm was found in women with the oldest hormonal status (postmenopausal period) (OR = 0.18; p<0.001), with osteoporosis in the family (OR = 0.37; p<0.001) and living in an agglomeration (OR = 0.68; p = 0.03). CONCLUSION: Interventions to increase physical activity, especially outdoors, may help reduce risk of osteoporosis, fractures and subsequent healthcare costs.

Bone mineral density in old age: the influence of age at menarche, menopause status and habitual past and present physical activity.

INTRODUCTION: In this study, the hypothesis that bone mineral density (BMD) of peri-, pre- and postmenopausal women is associated with the current level of habitual physical activity, as well as past physical activity, at the age of building peak bone mass, was tested. MATERIAL AND METHODS: The study involved 500 Polish women aged 40 to 70. For the assessment of BMD and bone mineral content (BMC) the densitometry method (dual-energy X-ray absorptiometry, DXA) of the forearm bone was used. The International Physical Activity Questionnaire (IPAQ) was used to assess the present level of physical activity. The assessment of past physical activity was related to adolescence. RESULTS: There was a significant, strong influence on the norm BMD in the distal forearm sections values in the distal forearm sections of such variables as: older age of the first menstruation (OR = 1.37; p = 0.002), sufficient present physical activity (OR = 1.57; p = 0.001), and particularly high past physical activity (OR = 6.77; p = 0.003). Significantly lower chances for the norm BMD dis were found in women with the oldest hormonal status (OR = 0.09; p < 0.001). In the proximal segment, the analogous conditions of the norm BMD, and in addition the chances for good mineralization, were increased by higher body mass index (OR = 1.11; p < 0.001). Sufficient present activity increased the chances of good forearm mineralization in the proximal part more than four times (OR = 4.2; p < 0.001), and a high level of past physical activity increased these chances several dozen times (OR = 69.9; p < 0.001). CONCLUSIONS: Physical activity proved to be one of the most important factors determining the statistically significant correct mineralization of bone tissue of women.

Bone Mineral Density in Adolescent Boys: Cross-Sectional Observational Study.

Physical inactivity of children can be a precursor of reduced bone mineral density, considered to be a typical problem only in old age. The aim of this study was to evaluate bone mineral density in 96 Polish boys aged 14-17 years with varied physical activity (swimmers, track and field athletes, non-athletes) and the effect of bone composition, birth weight and breastfeeding during infancy on bone parameters. Anthropometric and body composition measurements were performed according to the kinanthropometric standards. Bone parameters of the forearm were measured by means of dual-energy X-ray absorptiometry. Data on the infant's birth weight and the length of breastfeeding were collected during direct interviews with mothers. The strongest links with bone parameters were found for the type of physical activity and birth weight. Regardless of birth weight, track and field athletes had the most advantageous bone parameters (mainly sT-score prox values). Swimmers with normal or low birth weight had less favourable sT-score prox values than non-athletes. The type of physical activity proved to be an important determinant of bone parameters. Childhood and adolescence are important periods of bone development and increasing the content of bone mineral components, and the bone status in later years of life depends to a large extent on this period. The perinatal period, especially the correct birth weight of the child, not only has a significant effect on general health, but also on bone status.

Bone mineral density in young adults: the influence of vitamin D status, biochemical indicators, physical activity and body composition.

The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men. Physical activity has the most significant effect on bone status especially in men. PURPOSE: The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men. METHODS: One hundred subjects aged 19-24 years were included. Bone mineral density (BMD) in distal and proximal parts was evaluated by forearm densitometry. Body composition was analysed with the use of JAWON-Medical-x-scan. The following biochemical indicators were analysed: 25(OH) D and 1,25(OH)2D, magnesium, phosphorus, total cholesterol and triglycerides. Physical activity levels were assessed by interview. RESULTS: Significant correlations between BMD and physical activity, skeletal muscle mass and body fat percentage were revealed in men. Among women, considerably weaker correlations of BMD with body composition and physical activity were noted than in men. BMD in the distal part correlated only with lean body mass, soft lean mass and body fat percentage. The strongest relationship between physical activity and bone mineral status parameters was noted for BMD in men. In women, physical activity did not affect BMD. CONCLUSIONS: Physical activity has the most significant effect on bone status especially in men.

Can Anthropometric Variables and Maturation Predict the Playing Position in Youth Basketball Players?

Anthropometric diagnoses predict the most appropriate on-court position for a certain player and are important in the long-term planning of basketball training programs. This study provides anthropometric characteristics and body composition profiles of Polish youth national team players (U-14, U-15, U-16 and U-18). The aim of this research was to determine the somatic characteristics of basketball players regarding particular on-court positions. The sample population consisted of 109 elite basketball players, who played in national teams in four age categories: U-14, U-16, U-18 U-20. An analysis of the obtained results revealed differences between the younger (U-14, U-15 and U-16) and older groups (U-18 and U-20) in terms of length, width and circumference measurements and body mass (3.6-9.3%), as well as subcutaneous fat measured by the skinfold thickness method (14.3-33.7%). ANCOVA with maturity offset as the covariate variable showed differences in body height (p < 0.05, R2 = 0.74) and the arm span (p < 0.05, R2 = 0.87) between each playing position; the somatic measurements were greater for centers than for forwards and guards, and the measurements were greater for forwards than for guards. The somatic feature measurements also increased linearly with age. We can conclude that the arm span and body height are two major somatic factors that can predict center and guard playing positions for national team basketball players in all age categories from U-14 to U-20.

Bone mineral density, hand grip strength, smoking status and physical activity in Polish young men.

The human skeleton undergoes constant changes encompassing the phases of growth, consolidation and involution of the bone tissue. The aim of the research was to assess the relationship between bone mineral density (BMD) and such factors as hand grip strength, somatic structure or attitudes to tobacco smoking in men with different levels of physical activity. The study included 172 males aged 20-30 years. Mineral density and forearm bone mass were measured using the dual-energy X-ray absorptiometry method. Physical activity levels were assessed with the use of the International Physical Activity Questionnaire. Hand grip strength was measured with Jamar hand dynamometer. Attitudes towards smoking were assessed using the Global Adult Tobacco Survey. The correlation between a high level of physical activity among men and higher BMD and bone mass both in the distal and proximal parts of the forearm was statistically significantly greater compared to individuals with an insufficient level of physical activity. A better state of BMD and higher bone mass in both forearm bones was noted among non-smoking men. A high level of physical activity was the most significant predictor of BMD in the distal part of the forearm. The regression analysis in the proximal part revealed that body mass and a high level of physical activity were the most important predictors of BMD. The lack of physical activity was associated with more frequent occurrence of low bone mass in men. Tobacco smoking may be one of the most important risk factors of poor bone mineralization in young men.

Anthropometric Variables and Somatotype of Young and Professional Male Basketball Players.

BACKGROUND: Determining somatic models and profiles in young athletes has recently become a fundamental element in selecting basketball playing positions. The aim of this study was to assess the relationship between the body build of young and adult elite male basketball players at different playing positions. METHODS: Participants consisted of 35 young (age: 14.09 ± 0.30 years, n = 35) and 35 adult professional basketball players (age: 24.45 ± 5.40 years, n = 35) competing in elite leagues. The anthropometric characteristics assessed included body mass, body height, skinfolds, somatotypes, girths, and breadths. RESULTS: The centers in both age groups were significantly taller and heavier (p < 0.001) compared to forwards and guards. The greatest difference between categories were in the guards' personal height (from 169.36 to 186.68 = 17.32 cm). The guards from the professional team were closest in height to the forwards (difference = 7.17 cm) compared to young players where the difference between guards and forwards was 13.23 cm. Young competitors were more ectomorphic (2.12-3.75-4.17), while professional players were more mesomorphic (2.26-4.57-3.04). Significant criteria for center selection at professional level seems to be personal height and arm span ratio. CONCLUSIONS: The results indicate that the selection for basketball playing positions should include the analysis of body height and mass, shoulder breadth, humerus breadth, femur breadth and specifically for centers the difference between personal the height and arm span.