Rapid trabecular bone growth in puberty associated with stiffer arteries in adulthood - longitudinal study on healthy young males.

Longitudinal bone content data from puberty to adulthood was assessed in 102 healthy males and associations with arterial health in adulthood was analysed. Bone growth in puberty was related to arterial stiffening and final bone mineral content to decreased arterial stiffness. Relationships with arterial stiffness were dependent on the studied bone regions. INTRODUCTION: Our aim was to assess the relationships between arterial parameters in adulthood and bone parameters in several locations longitudinally from puberty to 18-years and cross-sectionally at 18-years. METHODS: 102 healthy male data from a 7-year follow-up study was used to analyse total body (TB), femoral neck (FN) and lumbar spine (LS) mineral content and density by DXA, carotid intima-media thickness (cIMT) by ultrasound, carotid-femoral pulse wave velocity (cfPWV) and heart rate adjusted augmentation index (AIxHR75) by applanation tonometry. RESULTS: Linear regression analysis revealed negative associations between LS bone mineral density (BMD) and cfPWV [ß=-1.861, CI -3.589, -0.132, p=0.035] which remained significant [ß=-2.679, CI -4.837, -0.522, p=0.016] after adjustment to smoking, lean mass, weight category, pubertal stage, physical fitness, and activity. For AIxHR75 similar results were present [ß=-0.286, CI -0.553, -0.020, p=0.035], but were dependent on confounders. Analysis on pubertal bone growth speed showed independent positive associations to AIxHR75 between Δ FN bone mineral apparent density (BMAD) [ß=672.50, CI 348.07, 996.93, p<0.001] and Δ LS BMAD [ß=700.40, CI 57.384, 1343.423, p=0.033]. Further analysis combining pubertal bone growth and adulthood BMC revealed that the relationships of AIxHR75 with LS BMC and ΔFN BMAD were independent of each other. CONCLUSION: Trabecular bone regions like lumbar spine and femoral neck, showed stronger relationships with arterial stiffness. Rapid bone growth in puberty is related to arterial stiffening, while final bone mineral content relates to decreased arterial stiffness. These results could indicate that bone metabolism is independently associated with arterial stiffness rather than bone and arteries just having common traits of growth and maturation.

Changes in irisin, inflammatory cytokines and aerobic capacity in response to three weeks of supervised sprint interval training in older men.

BACKGROUND: This study investigated the effects of supervised short-term sprint interval training (SIT) on circulating irisin, interleukin (IL)-6 and tumour necrosis factor (TNF)-α concentrations, and aerobic capacity and body composition values in healthy older men. METHODS: Eleven older men (63±8 years; 178.0±5.5 cm; 82.7±8.6 kg; 22.7±3.7% body fat) underwent SIT (6 repetitions of 30 s all-out cycling bouts with 4 min active recovery after each bout) three days a week for three consecutive weeks. Body composition measured by dual-energy X-ray absorptiometry, aerobic capacity assessed by direct peak oxygen consumption (VO2peak) test and morning fasting blood samples were obtained before and after a 3-week SIT intervention. RESULTS: Nine supervised SIT sessions moderately (effect size [ES] =0.65; P<0.05) increased irisin concentrations (from 135.40±28.73 to 154.20±47.09 ng.mL-1) together with moderate decreases (P<0.05) in IL-6 (ES=0.89; from 1.26±0.44 to 0.87±0.44 pg.mL-1) and TNF-α (ES=0.64; from 5.10±1.23 to 4.31±1.20 pg.mL-1) levels in older men. In addition, increase in VO2peak was significant but small (ES=0.25; P<0.05; from 36.0±7.1 to 37.8±6.7 mL.min.-1kg-1), while no changes (P>0.05) in body composition variables were observed after a short-term SIT period. CONCLUSIONS: A 3-week SIT intervention with only nine training sessions increased circulating irisin concentrations, improved inflammatory profile and aerobic capacity without changes in body composition in healthy older men. Accordingly, a short-term SIT programme is a time efficient alternative for traditional aerobic training to improve metabolic health and aerobic capacity in older adults.

Arterial Structure in 18-Year-Old Males Is Dependent on Physical Activity at 12 Years and Cumulative Cardiorespiratory Fitness From Puberty to Late Adolescence.

PURPOSE: To evaluate the long-term effect of body composition, physical activity, and cardiorespiratory fitness (CRF) from puberty on arterial health in late adolescent males. METHODS: The cumulative burden of physical activity (measured with accelerometer), CRF (VO2peak0.82), and body composition (body mass index, fat mass, and fat percentage) from puberty to late adolescence (sum of 4 time points from 12 to 18 y) was assessed in 102 males. Additional analysis on the first (T1) and last (T4) time points was performed. Intima-media thickness (IMT), carotid-femoral pulse wave velocity, and augmentation index adjusted to heart rate of 75 beats per minute (bpm) as dependent variables were measured at T4 and analyzed in multivariable regression models adjusted for known risk factors including maturation, blood pressure, and smoking habits. RESULTS: T1 and cumulative body composition measures were independently associated with IMT, while cumulative (ß = -0.011, P = .036) and T4 (ß = -0.0.031, P = .001) CRF revealed independent associations with IMT. Individuals with moderate to vigorous physical activity >60 minutes per day at T1 showed relationship (ß = -1.091, P = .026) with IMT independently of late adolescent physical activity. No significant relationship was present for arterial function. CONCLUSION: Arterial structure in adolescent males is associated with physical activity at 12 years while relationship with CRF can be seen in late adolescence and cumulatively from puberty to late adolescence.

The Associations of Body Image Perception with Serum Resistin Levels in Highly Trained Adolescent Estonian Rhythmic Gymnasts.

Rhythmic gymnasts (RGs) are more likely to be dissatisfied with their body mass and shape compared to untrained controls (UCs). However, due to the lack of information, the aim of this study was to investigate the associations of body image perception (BIP) with body composition, daily energy consumption and different blood biochemical markers in adolescent RGs compared to UCs. Thirty-three highly trained RG girls and 20 UC girls aged 14-18 years participated in this cross-sectional study. Height, body mass, body composition, energy intake, resting energy expenditure, training volume and different blood biochemical markers were measured. The body attitude test (BAT) was used to evaluate the BIP of the participants. There were no differences in the total BAT scores between the groups. In RGs, the BAT score correlated positively with the serum resistin level (r = 0.35; p = 0.047). A stepwise multiple regression analysis showed that 40.8% of the variability in the BAT score was determined by resistin and BMI. The association of BIP with resistin values was observed only in RGs. In conclusion, our findings add to the increasing evidence that resistin may be a link between BIP and body composition, most likely through fat mass, in adolescent female RGs.

Relationships of Bone Mineral Variables with Body Composition, Blood Hormones and Training Volume in Adolescent Female Athletes with Different Loading Patterns.

The aim of this investigation was to determine the relationships of areal bone mineral density (aBMD) and content (BMC) with body composition, blood hormone and training load variables in adolescent female athletes with different loading patterns. The participants were 73 healthy adolescent females (14-18 years), who were divided into three groups: rhythmic gymnasts (RG; n = 33), swimmers (SW; n = 20) and untrained controls (UC; n = 20). Bone mineral and body compositional variables were measured by dual-energy X-ray absorptiometry, and insulin-like growth factor-1 (IGF-1), estradiol and leptin were analyzed from blood samples. In addition, aerobic performance was assessed by a peak oxygen consumption test. No differences (p > 0.05) in weekly training volume were observed between rhythmic gymnasts (17.6 ± 5.3 h/week) and swimmers (16.1 ± 6.9 h/week). Measured areal bone mineral density and bone mineral content values were higher in rhythmic gymnasts compared with other groups (p < 0.05), while no differences (p > 0.05) in measured bone mineral values were seen between swimmers and untrained control groups. Multiple regression models indicated that IGF-1 alone explained 14% of the total variance (R2 × 100) in lumbar spine aBMD, while appendicular muscle mass and training volume together explained 37% of the total variance in femoral neck BMC in the rhythmic gymnast group only. In swimmers, age at menarche, estradiol and appendicular muscle mass together explained 68% of the total variance in lumbar spine BMC, while appendicular muscle mass was the only predictor and explained 19 to 53% of the total variance in measured bone mineral values in untrained controls. In conclusion, adolescent rhythmic gymnasts with specific weight-bearing athletic activity present higher areal bone mineral values in comparison with swimmers and untrained controls. Specific training volume together with appendicular muscle mass influenced cortical bone development at the femoral neck site of the skeleton in rhythmic gymnasts, while hormonal values influenced trabecular bone development at the lumbar spine site in both athletic groups with different loading patterns.

Serum sclerostin concentration is associated with specific adipose, muscle and bone tissue markers in lean adolescent females with increased physical activity.

OBJECTIVES: Sclerostin is an important regulator of bone mass involving the Wnt/ß-catenin signalling pathway. Relatively few studies have investigated the relationships of circulating sclerostin levels with adiposity-related and muscle-related biochemical factors in individuals with increased energy metabolism. The aim of this study was to investigate the associations of circulating sclerostin with adipokines, myokines, osteokines and body composition values in lean adolescent females with increased physical activity. METHODS: A total of 73 adolescent females who were physically active and aged 14-18 years old participated in the study. Sclerostin, leptin, resistin, tumour necrosis factor (TNF)-α, interleukin (IL)-6, irisin, osteocalcin, C-terminal telopeptide of type I collagen (CTx), insulin-like growth factor (IGF)-1 and insulin were obtained from fasting blood samples. Body composition was measured by dual-energy X-ray absorptiometry (DXA) and analyzed for body fat mass, lean body mass, bone mineral content and muscle mass. RESULTS: Serum sclerostin (117.9 ± 60.3 pg/mL) was correlated with age, age at menarche, body fat, muscle mass, training activity, leptin, TNF-α, irisin, osteocalcin, CTx and IGF-1. Multivariate linear regression analysis demonstrated that fat mass (ß = 0.434; p = 0.001), leptin (ß = -0.308; p = 0.015), irisin (ß = 0.227; p = 0.024) and CTx (ß = 0.290; p = 0.031) were the most important predictors of serum sclerostin concentration. CONCLUSIONS: Bone-derived sclerostin is associated with specific adipokine, myokine and osteokine values in lean adolescent females with increased physical activity. These results suggest that the interactions between bone, adipose and muscle tissues could also be associated with circulating sclerostin concentrations.

Serum sclerostin and cytokine responses to prolonged sculling exercise in highly-trained male rowers.

This study examined sclerostin and cytokine responses to an endurance training session in male single sculling rowers. Sixteen highly trained rowers performed a 2-h rowing exercise (distance: 23.8 ± 0.9 km; heart rate: 138 ± 8  beats.min-1; intensity: 79.8 ± 2.1% of the anaerobic threshold). Rowing resulted significant increment (p < 0.05) in sclerostin (36%), interleukin (IL)-6 (345%), IL-10 (129%) and monocyte chemoattractant protein-1 (MCP-1) (132%), while increases in irisin (6%) and tumour necrosis factor-α (3%) were not significant (p > 0.05). There was a correlation between the pre-to-post-exercise increase in sclerostin and the distance covered (r = 0.67; p = 0.005) as a marker of energy expenditure, and weekly training volume (r = 0.66; p = 0.005) as a marker of training stress. Post-exercise gain in MCP-1 was the most important predictor of post-exercise gain in sclerostin (ß = 0.543; p = 0.040). In conclusion, acute non-impact rowing training session with a total body mode induced increases in sclerostin and also in IL-6, IL-10 and MCP-1 concentrations, while post-exercise gain in MCP-1 was the main determinant of post-exercise gain in sclerostin. Exercise-induced increase in sclerostin could be regarded as a signal for metabolic reaction to the energy cost of acute exercise in rowers.

Irisin and inflammatory cytokines in elite male rowers: adaptation to volume-extended training period.

BACKGROUND: This study examined the effect of 6-month volume-extended training period on irisin and inflammatory cytokine concentrations in elite male rowers. METHODS: Nine elite male rowers (25.3±6.5 yrs; 190.6±5.1 cm; 93.4±7.5 kg; 14.6±2.6% body fat; maximal oxygen consumption [VO2max]: 64.0±3.5 mL.min.-1kg-1) participated in this study. Body composition, VO2max and blood biochemical markers were assessed before and after training period. Venous blood samples were analyzed for irisin, interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-γ, tumor necrosis factor-α, IL-1α, IL-1ß, monocyte chemoattractant protein-1 and epidermal growth factor (EGF). RESULTS: Average weekly training volume was significantly higher (P<0.05) during the 6 months of heavy training compared to relative rest (11.6±1.4 h.week-1 vs. 18.4±1.0 h.week-1), while training intensity remained the same. At the end of training period, body fat% was significantly decreased, and fat free mass and maximal aerobic power significantly increased. Irisin was not changed (P>0.05) as the result of 6-month heavy training period, while training induced significant (P<0.05) increases and decreases in IL-10 and EGF values, respectively. CONCLUSIONS: Serum irisin concentration was not sensitive to a significant increase in weekly training volume during the volume-extended training period in elite male rowers. An increase in training stress was accompanied by the increase in IL-10 and a decrease in EGF levels, and these inflammatory cytokines could be regarded as markers of heavy training stress during the typical preparatory period in elite male rowers.

Sclerostin, preadipocyte factor-1 and bone mineral values in eumenorrheic adolescent athletes with different training patterns.

INTRODUCTION: The specific aims of the study were to compare possible differences in sclerostin and preadipocyte factor-1 (Pref-1) between rhythmic gymnasts (RG), swimmers (SW) and untrained controls (UC), and to investigate the relationships of sclerostin and Pref-1 with bone mineral characteristics in studied groups. MATERIALS AND METHODS: This study included 62 eumenorrheic adolescents (RG = 22; SW = 20; UC = 20). Bone mineral and body composition characteristics were measured by dual-energy X-ray absorptiometry, and sclerostin, Pref-1, osteocalcin and C-terminal telopeptide of type I collagen (CTx) were measured. RESULTS: Sclerostin was higher (P = 0.001) in RG (129.35 ± 51.01 pg/ml; by 74%) and SW (118.05 ± 40.05 pg/ml; by 59%) in comparison with UC (74.32 ± 45.41 pg/ml), while no differences (P = 0.896) were seen in Pref-1 (RG: 1.42 ± 0.16 ng/ml; SW: 1.41 ± 0.20 ng/ml; UC: 1.39 ± 0.26 ng/ml) between groups. Osteocalcin (RG: 7.74 ± 4.09 ng/ml; SW: 8.05 ± 4.18 ng/ml; UC: 7.04 ± 3.92 ng/ml; P = 0.843) and CTx (RG: 0.73 ± 0.22 ng/ml; SW: 0.64 ± 0.16 ng/ml; UC: 0.62 ± 0.20 ng/ml; P = 0.173) were not different between groups. Sclerostin correlated (P < 0.05) with whole-body bone mineral content (r = 0.61) and lumbar spine (LS) areal bone mineral density (aBMD) (r = 0.43) in RG, and femoral neck aBMD (r = 0.45) in UC. No correlation was found between sclerostin and bone mineral values in SW, and Pref-1 was not correlated with any bone mineral characteristics in studied groups. Sclerostin was the independent variable that explained 14% of the total variance (R2 × 100) in LS aBMD value only in RG. CONCLUSIONS: Adolescent athletes have higher sclerostin compared to UC. Sclerostin was correlated with bone mineral values and predicted areal bone mineral density in RG.

Effects of whole-body vibration training on bone density and turnover markers in adolescent swimmers.

Background Whole-body vibration training has recently been proposed as a complementary training modality to improve the bone health of adolescent swimmers. However, there is no longitudinal study regarding the effects of this training combination on bone metabolism. Therefore, the main goal was to analyze the effects of swimming and vibration training on bone turnover markers during adolescence. Methods The present study included 68 adolescent swimmers and 41 normoactive controls (CON). Swimmers were randomly selected to either continue with their regular swimming training (SWI) or participate in an additional vibration protocol (VIB). Anthropometric measurements and serum level determinations of osteocalcin (OC), procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide crosslaps (CTX) were performed before and after the 6-month intervention. Results Statistically significant group by time interactions were found for both bone formation markers. VIB showed a decrease over time in OC (baseline: 101.4 µg/mL, follow-up: 82.8 µg/mL, p < 0.05) and P1NP (baseline: 528.4 µg/mL, follow-up: 389.0 µg/mL, p < 0.05) and SWI had analogous reductions in P1NP (baseline: 685.8 µg/mL, follow-up: 542.0 µg/mL, p < 0.05), whereas CON experienced an increase in OC levels (baseline: 94.4 µg/mL, follow-up: 103.4 µg/mL, p < 0.05). After stratifying the sample according to the pubertal status, similar interactions were observed. Conclusions The combination of swimming training and this particular vibration protocol led to a decrease in bone formation markers, especially during early puberty. Whole-body vibration might not induce an osteogenic stimulus in adolescent swimmers.

Inflammatory markers and bone mass in children with overweight/obesity: the role of muscular fitness.

OBJECTIVES: To examine which inflammatory markers are associated with bone mass and whether this association varies according to muscular fitness in children with overweight/obesity. METHODS: Plasma interleukin-1ß (IL-1ß), IL-6, tumor necrosis factor-α (TNF-α), epidermal growth factor, vascular endothelial growth factor A (VEGF), and C-reactive protein were analyzed in 55 children aged 8-11 years. A muscular fitness score was computed. Bone mineral content (BMC) of the total body-less head (TBLH) and lumbar spine (LS) were assessed using dual-energy x-ray absorptiometry. RESULTS: IL-6 (ß = -0.136) and VEGF (ß = -0.099) were associated with TBLH BMC, while TNF-α (ß = -0.345) and IL-1ß (ß = 0.212) were associated with LS BMC (P < 0.05). The interaction effect of muscular fitness showed a trend in the association of VEGF with TBLH BMC (P = 0.122) and TNF-α with LS BMC (P = 0.057). Stratified analyses by muscular fitness levels showed an inverse association of VEGF with TBLH BMC (ß = -0.152) and TNF-α with LS BMC (ß = -0.491) in the low-fitness group, while no association was found in the high-fitness group. CONCLUSION: IL-6, VEGF, TNF-α, and IL-1ß are significantly associated with bone mass. Higher muscular fitness may attenuate the adverse effect of high VEGF and TNF-α on bone mass.

Resistin concentration is inversely associated with objectively measured physical activity in healthy older women.

Regular physical activity (PA) has been associated with decreased risk of many chronic diseases and increased longevity among older adults. In addition, ageing has been associated with higher levels of different inflammatory biomarkers while the association between inflammatory biomarkers and PA has remained controversial. The aim of the current investigation was to examine the association between blood biomarkers and objectively assessed PA among a sample of healthy older women with different levels of PA engagement. A total of 81 healthy women were recruited. Study participants were allocated to three groups according to accelerometer-obtained PA data. Body composition was assessed with dual-energy X-ray absorptiometry. Fasting blood samples were collected for the measurement of resistin, leptin, tumour necrosis factor alpha (TNFα) and C-reactive protein (CRP) concentrations. There were no significant differences between groups for resistin, leptin, TNFα and for CRP concentrations; however, higher moderate-to-vigorous physical activity (MVPA) groups tended to have lower level of blood biomarker concentrations. There was a significant negative relationship between resistin and steps per day. Inverse association between leptin and MVPA was significant after controlling for age. In multivariate stepwise linear regression analysis, steps per day were the strongest independent predictor for resistin, whereas for leptin, TNFα and CRP the strongest independent predictor was whole body fat mass. In conclusion, this study demonstrated negative association between resistin concentration and steps per day. Sedentary time and light PA had no relationship with resistin, leptin, TNFα or CRP concentrations.

Circulating Inflammatory Cytokine Responses to Endurance Exercise in Female Rowers.

This investigation examined the effects of acute rowing exercise on a panel of 12 different inflammatory cytokines. Fifteen female rowers (18.3±1.6 yrs; 172.0±5.0 cm; 67.5±8.8 kg; maximal oxygen consumption [VO2max]: 47.2±7.9 ml.min.-1kg-1) completed a 1-h endurance exercise (distance: 12.1±1.1 km; energy expenditure [EE]: 639±69 kcal; heart rate: 151±7 beats.min-1; intensity: 79.6±3.5% of the second ventilatory turn point). Venous blood samples were analysed for interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor (VEGF), interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), IL-1α, IL-1ß, monocyte chemoattractant protein-1 (MCP-1) and epidermal growth factor (EGF) concentrations. Rowing exercise resulted increment (P<0.05) in IL-6, IL-8, VEGF and MCP-1. Exercise metabolic demand variables such as rating of perceived exertion (r=0.61), distance covered (r=0.60) and EE (r=0.57) were related (P<0.05) to changes in VEGF concentration. Cardiorespiratory fitness as measured by VO2max was correlated with changes in IL-6 (r=-0.55; P<0.05) level. In conclusion, acute exercise-induced inflammatory reaction was induced by a significant increase in IL-6, IL-8, VEGF and MCP-1 concentrations. Variance in exercise-induced increases in inflammatory cytokines in response to prolonged endurance exercise was characterised by exercise metabolic demand and cardiorespiratory fitness measures in female rowers.

The Impact of Physical Activity on Serum Inflammatory Markers in Overweight Pubertal Boys: 24-Month Follow-Up Study.

PURPOSE: To investigate the differences in the pattern of changes in serum inflammatory cytokines measured annually over a 24-month period, between less active and more active overweight boys. PARTICIPANTS/METHODS: In total, 25 pubertal overweight boys were divided by their moderate to vigorous physical activity (MVPA) levels into 2 groups: less active group (LAG; n = 10; MVPA < 60 min/d) and more active group (MAG; n = 15; MVPA > 60 min/d). Physical activity was measured by 7-day accelerometry. Serum concentration of 13 inflammatory cytokines [interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, IL-1α, IL-1ß, vascular endothelial growth factor, interferon-γ, tumor necrosis factor-α, monocyte chemotactic protein-1, epidermal growth factor, and C-reactive protein] was measured at baseline (T0), after 12 months (T1), and after 24 months (T2) from fasting blood samples. RESULTS: Serum IL-6 level was significantly higher [LAG: 1.27 (0.86, 1.98) pg/mL; MAG: 0.80 (0.52, 0.84) pg/mL] at T0 and IL-8 level [LAG: 10.26 (8.80, 11.64) pg/mL; MAG: 7.42 (6.10, 9.54) pg/mL] at T2 in LAG compared with MAG. The changes over the study period varied between different inflammatory markers. None of the slopes of any measured markers were statistically different between the LAG and MAG, although the slopes of interferon-γ and IL-10 tended to be different between the groups. CONCLUSIONS: The pattern of changes over the study period varied between different inflammatory markers, but these changes were not different between the MVPA groups. More longitudinal studies are needed to investigate whether IL-6, IL-8, IL-10, and interferon-γ would be the choice of inflammatory markers to study the associations between obesity and physical activity in future.

Body composition and inflammatory markers in pubertal girls: Comparison between athletes and non-athletic controls.

Various inflammation parameters are increased with childhood obesity, but few comparable data are found in lean growing athletes. This study aims to characterize differences in 12 simultaneously measured inflammatory parameters between pubertal rhythmic gymnasts (RG) and untrained controls (UC), and to examine the relationship between body composition and inflammatory markers. Sixty 10-12-year-old girls were divided into RG (n = 30) and UC (n = 30). Fat mass (FM) and fat free mass (FFM) were measured by dual-energy X-ray absorptiometry. Leptin and 12 inflammatory parameters (interleukin [IL]-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-gamma [IFN-γ], tumor necrosis factor-alpha, IL-1α, IL-1ß, monocyte chemotactic protein-1 and epidermal growth factor) were measured from fasting blood samples. No differences were seen in 12 inflammatory markers between studied groups. As expected, leptin (RG: 2.4 ± 1.1; UC: 7.6 ± 4.2 ng ml-1) and FM (RG: 7.3 ± 2.3; UC: 11.8 ± 5.1 kg) were lower (p < .05) in RG compared to UC. In the whole group of lean pubertal girls, 69.0% of the variability in body FM was determined by leptin, and 11.2% of the variability in body FFM was explained by IFN-γ. In conclusion, measured 12 inflammatory biomarkers were not different between RG and UC, despite lower leptin and FM in RG. In lean pubertal girls, IFN-γ was independently associated with FFM, and leptin with FM.

Changes in inflammatory markers in estonian pubertal boys with different BMI values and increments: A 3-Year Follow-Up Study.

OBJECTIVE: Serum inflammatory markers could help to identify those boys with overweight (OWB) who gain weight more extensively during puberty. This study aimed to examine the longitudinal changes in different serum inflammatory markers through puberty in boys with different BMI values and increments. METHODS: Twenty-six OWB and 29 normal-weight boys (NWB) were followed yearly for 3 years to measure changes in BMI and serum concentrations of 12 inflammatory markers. RESULTS: OWB had higher (P < 0.033) baseline interleukin (IL)-6, IL-8, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and IL-1α concentrations in comparison with NWB. Over the 3-year period, IFN-γ (P = 0.0001) and TNF-α (P = 0.0042) decreased more in OWB compared to NWB. Serum IL-8, monocyte chemoattractant protein (MCP)-1, and leptin increased further in those OWB who gained BMI more extensively through puberty compared to OWB who gained weight at slower rates (P < 0.033). CONCLUSIONS: Serum IFN-γ and TNF-α levels decreased more during pubertal years in OWB compared to NWB, indicating that pubertal maturation itself may have a favorable impact on the inflammation of obesity. Serum IL-8, MCP-1, and leptin could help to identify OWB who gain BMI more extensively during pubertal years.

Body composition, maximal aerobic performance and inflammatory biomarkers in endurance-trained athletes.

This study was designed to examine the relationships between body composition, cardiorespiratory fitness and simultaneously measured inflammatory parameters in endurance-trained athletes. In 20 well-trained rowers (19·0 ± 2·9 years; 185·6 ± 4·8 cm; 85·7 ± 10·8 kg; 17·1 ± 5·1% body fat; maximal oxygen consumption [VO2 max]: 63·9 ± 8·5 ml min-1  kg-1 ), body composition was measured by dual-energy X-ray absorptiometry and cardiorespiratory fitness by direct VO2 max test. Twelve inflammatory factors [interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-gamma (IFN-γ), tumour necrosis factor-alpha, IL-1α, IL-1ß, monocyte chemoattractant protein-1 (MCP-1), epidermal growth factor (EGF)] were analysed from serum samples. Serum IFN-γ was related (P<0·05) to fat-free mass (FFM) (r = -0·56) and muscle mass (r = -0·50). The stepwise regression analysis showed that IFN-γ explained 27·5%, and IFN-γ and IL-6 together explained 39·8% of the variability of FFM, while IFN-γ explained 21·1%, and IFN-γ together with EGF explained 36·6% of the variability of muscle mass in male rowers. Serum IL-8 (r = -0·65) and VEGF (r = -0·48) correlated (P<0·05) with VO2 max kg-1 . Serum IL-8 explained 38·5% of the variability of VO2 max kg-1 . Significant correlations were also found among several inflammatory parameters, indicating that various inflammatory cytokines act on the body as an ensemble. In conclusion, this cross-sectional study in endurance-trained male rowers showed that FFM and muscle mass were negatively correlated with serum IFN-γ level, whereas cardiorespiratory fitness was negatively related to serum IL-8 level.

Longitudinal associations between bone and adipose tissue biochemical markers with bone mineralization in boys during puberty.

BACKGROUND: We investigated longitudinal relationships between the biochemical markers of bone and adipose tissue with bone mineral content (BMC), bone mineral density (BMD), moderate-to-vigorous physical activity (MVPA) and sedentary time (SED) in pubertal boys. METHODS: Ninety-six boys (11.9 ± 0.6 years old) were measured at baseline, after 12 and 24 months. Body composition (fat mass [FM], lean body mass [LBM]), and whole body (WB), lumbar spine (LS) and femoral neck (FN) BMD and BMC were assessed. Additionally, serum leptin, adiponectin, osteocalcin (OC) and C-terminal telopeptide of type I collagen (CTX) were measured. RESULTS: OC had a strong longitudinal inverse effect on changes in WB_BMD (p < 0.001) and LS_BMD (p = 0.021), while CTX had an inverse effect only on changes in FN_BMD (p = 0.011). Leptin had an inverse effect on changes in WB_BMC/WB_BMD (p = 0.001), FN_BMD (p = 0.002) and LS_BMD (p = 0.001). MVPA showed a longitudinal inverse effect on changes in leptin (p = 0.030), however no longitudinal effect of SED to biochemical markers of bone and adipose tissue was found. CONCLUSIONS: Bone metabolism markers have negative effect on bone mineral accrual during puberty. Increases in MVPA affect leptin, suggesting a positive link of MVPA through leptin metabolism on increases in bone mineralization during puberty.

Adipocytokines and bone metabolism markers in relation to bone mineral values in early pubertal boys with different physical activity.

BACKGROUND: We aimed to examine the associations of adipocytokines and circulating bone metabolism markers with bone mineral parameters in early pubertal boys with different physical activity level. METHODS: Eighty-six early pubertal boys were divided into active and non-active boys according to the accumulated moderate-to-vigorous physical activity (MVPA) level. Body composition and bone mineral parameters were assessed and testosterone, leptin, adiponectin, osteocalcin (OC), and C-terminal telopeptide of type I collagen (CTX) were measured. RESULTS: Active subjects had significantly lower (p<0.05) body mass, body mass index (BMI), fat mass (FM), leptin, and sedentary time values, while non-active subjects had lower (p<0.05) vigorous physical activity level and femoral neck bone mineral density (FN-BMD). OC contributed to the models in physically active group and explained 6.6% and 9.7% of variance in whole body (WB) [F(5,44)=10.847; p<0.001] and lumbar spine bone mineral content (LS-BMC) [F(5,44)=4.158; p=0.004], respectively. No other biochemical parameters were found to be related to bone mineral parameters in either the active or non-active group. CONCLUSIONS: Bone metabolism markers were positively correlated with bone mineral values only in active pubertal boys. Leptin and adiponectin were not related to bone mineral parameters in active and non-active pubertal boys.

Acute inflammatory response to prolonged sculling in competitive male rowers.

BACKGROUND: This study examined the effects of a prolonged low-intensity single scull rowing exercise on a complex of 12 different inflammatory cytokines in rowers. METHODS: Twenty male rowers (19.0±2.9 yrs; 185.6±4.8 cm; 85.7±10.8 kg; 17.1±5.1% body fat; maximal oxygen consumption [VO2max]: 63.9±8.5 mL.min.-1kg-1) completed a rowing training session lasting about 2-h (distance: 21.4±1.8 km; heart rate [HR]: 139±8 beats.min-1; intensity: 79.9±3.6% of the anaerobic threshold) followed by a 30-min rest. Venous blood samples were collected before and after on-water rowing, and analyzed for blood white cell count (WBC), high sensitive C-reactive protein (hsCRP), and 12 inflammatory cytokines (interleukin [IL]-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-gamma, tumor necrosis factor-alpha, IL-1α, IL-1ß, monocyte chemotactic protein-1 [MCP-1], epidermal growth factor). RESULTS: Exercise induced significant (P<0.05) increment in WBC, hsCRP, IL-6, IL-10 and MCP-1 concentrations. The long-distance sculling intensity variables such as the average rating of perceived exertion, HR and blood lactate were correlated with changes in IL-8, IL-1α and IL-1ß levels (r=0.47 to r=0.59; P<0.05). Maximal aerobic performance variables (VO2max and maximal aerobic power) were related to changes in IL-2, IL-4, IL-8 and IL-1ß levels (r=-0.45 to r=-0.54; P<0.05). CONCLUSIONS: Acute exercise-induced inflammatory reaction was reflected by a significant increase in serum IL-6, IL-10 and MCP-1 levels. Variance in exercise-induced increases in inflammatory markers in response to 2-h of endurance exercise was explained by aerobic performance and exercise intensity levels in competitive male rowers.