How Different Loading Sports and a 9-Month Plyometric Intervention Programme Affect Bone Turnover Markers During Adolescence: The PRO-BONE Study

This is the final version. Available on open access from MDPI via the DOI in this recordPresented at the 9th Greek Conference of Biochemistry and Physiology of Exercise, Thessaloniki, Greece, 18–20 October 2019Aim: The purpose of the present study was to (1) investigate the cross-sectional (baseline) and longitudinal (12 months) effects of football (weight-bearing sport), swimming and cycling (non-weight-bearing sports), and an active control group on bone turnover markers in adolescent males and (2) examine the effect of a 9-month progressive jumping intervention programme on bone turnover in the sports groups of adolescent males. Materials & Methods: A total of 105 adolescent males (30 footballers, 37 swimmers, 26 cyclists, and 12 active controls), aged 12 to 14 years at baseline, were measured at baseline (T0), after 1 year of sport-specific training (T1) and following a 9-month progressive jumping intervention programme (T2). Bone turnover was measured using serum N-terminal propeptide of procollagen type I (PINP) as bone formation marker and isomer of the carboxy-terminal telopeptide of type 1 collagen (CTX-I) as bone resorption marker. Bone turnover rate and balance were estimated using the multiple of medians logarithmic equations of PINP and CTX-I. Results: At T0 there were no significant differences between groups in any of the biochemical markers. At T1 PINP was significantly higher in footballers than swimmers (3.3%) and cyclists (6.0%). Cyclists had significantly lower PINP (5.1%) and CTX-I (14.8%) than controls. In swimmers, there was a significant decrease in PINP (5.8%) and a significant increase in CTX-I (9.8%) from T0 to T1. In cyclists, PINP significantly decreased (7.2%) and CTX-I non-significantly increased (4.3%) from T0 to T1. At T2, PINP was reduced in all non-intervention sport groups (4.4% in swimmers, 3.3% in footballers, and 4.2% in cyclists). CTX-I was reduced by 3.8% in swimmers and cyclists who did not perform the intervention. Conclusions: The present study showed that at baseline there were no differences between groups in bone turnover, but after 1 year of sport-specific training bone turnover was significantly improved in footballers and controls compared to swimmers and cyclists. Following the 9-month jumping intervention bone turnover significant declined in the intervention groups of cycling and swimming. By contrast, bone formation significantly decreased in footballers and the control groups, and bone resorption significantly decreased in the non-intervention groups of cycling and swimming

A 9-month Jumping Intervention to Improve Bone Acquisition in Adolescent Male Athletes: The PRO-BONE Study

This is the author acepted manuscript. The final version is available via the DOI in this recordAnnual Meeting of the American College of Sports Medicine (ACSM), 29 May - 2 June 2018, Minneapolis, USA. G-21 Thematic Poster - Bone Quality in Athletes and Special Population

The effect of a high-impact jumping intervention on bone mass, bone stiffness and fitness parameters in adolescent athletes

This is the final version. Available on open access from Springer via the DOI in this record.This study demonstrates that a 9-month jumping intervention can improve bone mass gains and physical fitness performance in adolescent males participating in non-osteogenic sports, such as swimming and cycling. PURPOSE: To examine the effect of a jumping intervention on bone mass, bone stiffness and fitness parameters in adolescents involved in different sports. METHODS: Ninety-three adolescent male swimmers (SWI), footballers (FOO) and cyclists (CYC) were randomised to intervention (INT) and sport (INT-SWI = 19, INT-FOO = 15, INT-CYC = 14) or sport only (CON-SWI = 18, CON-FOO = 15, CON-CYC = 12) groups. The 9-month jumping intervention consisted of 3 levels (12 weeks each) of 20 repetitions per set of counter movement jumps (CMJ) using adjustable weight vests (level 1 = 20 CMJ jumps/set, 0 kg, 3 sets/day, 3 times/week; level 2 = 20 CMJ jumps/set, 2 kg, 4 sets/day, 3 times/week; level 3 = 20 CMJ jumps/set, 5 kg, 4 sets/day, 4 times/week). Total body bone mineral content (BMC) at total body less head (TBLH) was measured using dual-energy X-ray absorptiometry and bone stiffness using quantitative ultrasound. Fitness was assessed using the 20-m shuttle run (20mSRT), CMJ and standing long jump (SLJ) tests. RESULTS: INT-SWI had significantly higher increase in BMC legs and bone stiffness compared to CON-SWI (4.2-12.7%). INT-CYC had significantly higher increase in BMC at TBLH and legs and bone stiffness compared to CON-CYC (5.0-12.3%). There were no significant differences between INT-FOO and CON-FOO in any bone outcomes (0.9-3.9%). The increase in CMJ performance was significantly higher in INT-SWI (3.1 cm) and INT-CYC (3.2 cm) compared to CON-SWI and CON-CYC groups, respectively. CONCLUSIONS: A 9-month jumping intervention can improve bone mass, bone stiffness and muscular fitness in adolescent males participating in non-osteogenic sports, such as swimming and cycling. CLINICAL TRIAL REGISTRATION: ISRCTN17982776.European Union Seventh Framework Programme (FP7/2007–2013

A 9-month jumping intervention to improve bone geometry in adolescent male athletes

This is the author accepted manuscript. The final version is available from Lippincott, Williams & Wilkins via the DOI in this record.PURPOSE: Sports have different effects on bone development and effective interventions to improve bone health of adolescent athletes are needed. The purpose of the study was to investigate the effect of a 9-month jumping intervention on bone geometry and metabolism in adolescent male athletes METHODS: Ninety-three adolescent (14.1 years old) male swimmers (SWI), footballers (FOO) and cyclists (CYC) were randomized to an intervention and sport (INT-SWI=19, INT-FOO=15, INT-CYC=14) or sport only (CON-SWI =18, CON-FOO =15, CON-CYC =12) groups. Cross-sectional area (CSA), cross-sectional moment of inertia (CSMI) and section modulus (Z) at the femoral neck were assessed using hip structural analysis, and trabecular texture of the lumbar spine using trabecular bone score (TBS). Bone mineral content (BMC) at femoral neck and lumbar spine was assessed using dual-energy x-ray absorptiometry. Serum N-terminal propeptide of procollagen type I (PINP), isomer of the Carboxi-terminal telopeptide of type 1 collagen (CTX-I), total serum calcium and 25 hydroxyvitamin D [25(OH)D] were analysed. RESULTS: INT-CYC acquired significantly higher lumbar spine BMC (4.6 %) and femoral neck BMC (9.8 %) than CON-CYC. INT-CYC acquired significantly higher CSA (11.0 %), CSMI (10.1 %) and TBS (4.4 %) than CON-CYC. INT-SWI acquired significantly higher femoral neck BMC (6.0 %) and CSMI (10.9 %) than CON-SWI. There were no significant differences between INT-FOO and CON-FOO in any bone outcomes. PINP significantly decreased in CON-SWI, INT-FOO, CON-FOO and CON-CYC. CTX-I significantly decreased in CON-SWI and CON-CYC. 25(OH)D significantly increased in INT-CYC, CON-CYC, INT-FOO and CON-FOO. CONCLUSIONS: A 9-month jumping intervention improved bone outcomes in adolescent swimmers and cyclists, but not in footballers. This intervention might be used by sports clubs to improve bone health of adolescent athletes.The research leading to these results has received funding from the European Union Seventh Framework Programme ([FP7/2007-2013] under grant agreement n°. PCIG13-GA-2013-618496

Effect of a program of short bouts of exercise on bone health in adolescents involved in different sports: the PRO-BONE study protocol

This is the author accepted manuscript. The final version is available from BioMed Central via the DOI in this record.Background: Osteoporosis is a skeletal disease associated with high morbidity, mortality and increased economic costs. Early prevention during adolescence appears to be one of the most beneficial practices. Exercise is an effective approach for developing bone mass during puberty, but some sports may have a positive or negative impact on bone mass accrual. Plyometric jump training has been suggested as a type of exercise that can augment bone, but its effects on adolescent bone mass have not been rigorously assessed. The aims of the PRO-BONE study are to: 1) longitudinally assess bone health and its metabolism in adolescents engaged in osteogenic (football), non-osteogenic (cycling and swimming) sports and in a control group, and 2) examine the effect of a 9 month plyometric jump training programme on bone related outcomes in the sport groups. Methods/Design: This study will recruit 105 males aged 12-14 years who have participated in sport specific training for at least 3 hours per week during the last 3 years in the following sports groups: football (n=30), cycling (n=30) and swimming (n=30). An age-matched control group (n=15) that does not engage in these sports more than 3 hours per week will also be recruited. Participants will be measured on 5 occasions: 1) at baseline; 2) after 12 months of sport specific training where each sport group will be randomly allocated into two sub-groups: intervention group (sport + plyometric jump training) and sport group (sport only); 3) exactly after the 9 months of intervention; 4) 6 months following the intervention; 5) 12 months following the intervention. Body composition (dual energy X-ray absorptiometry, air displacement plethysmography and bioelectrical impedance), bone stiffness index (ultrasounds), physical activity (accelerometers), diet (24 h recall questionnaire), pubertal maturation (Tanner stage), physical fitness (cardiorespiratory and muscular) and biochemical markers of bone formation and resorption will be measured at each visit. Discussion: The PRO-BONE study is designed to investigate the impact of osteogenic and non-osteogenic sports on bone development in adolescent males during puberty, and how a plyometric jump training programme is associated with body composition parameters.European Union Seventh Framework Programme [FP7/2007-2013

Effect of maturational timing on bone health in male adolescent athletes engaged in different sports: The PRO-BONE study

This is the author accepted manuscript. the final version is available from Elsevier via the DOI in this recordObjectives: To describe differences in bone outcomes according to biological age in male athletes participating in osteogenic (OS) or non-osteogenic (NOS) sports. Design: Longitudinal (12-months). Methods: 104 adolescents (12–14 years) were measured at baseline and after 1y: OS group (n = 37 football or soccer players) and NOS group (n = 39 swimmers, n = 28 cyclists). Years from peak height velocity (PHV, −2 to +2) was used as a maturational landmark. Bone mineral content (BMC) was assessed using DXA. Hip structural analysis estimated cross-sectional area (CSA), cross-sectional moment of inertia (CSMI) and section modulus (Z) at the femoral neck (FN). Trabecular bone score (TBS) estimated lumbar spine (LS) texture. Quantitative ultrasound measured bone stiffness. Multilevel regression models adjusted by hours of training were fitted. Results: Compared to NOS, OS had significantly greater total body (less head) BMC from PHV to +2 years from PHV (from 9.5% to 11.3%, respectively); LS BMC from −1 years from PHV to PHV (from 9.8% to 9.9%); hip BMC (from 11.6% to 22.9%), FN BMC (from 12.0% to 15.9%), TBS (from 4.2% to 4.8%) and stiffness index (from 11.9% to 23.3%) from −1 years from PHV to +2 years from PHV; and CSA (from 8.4% to 18.8%), Z (from 5.5% to 22.9%) and CSMI (from 10.6% to 23.3%) from −2 years from PHV to +2 years from PHV. There was a significant trend for the between-group differences to increase with biological age except for LS BMC and TBS. Conclusions: These findings underline the differential bone response to different sports throughout the years surrounding PHV in male adolescent athletes. Clinical trial registration: ISRCTN17982776.European Union Seventh Framework ProgrammeUniversity of Castilla-La ManchaUniversity of Granad

Growth, Maturation, and Physical Fitness

This is the author accepted manuscript. The final version is available from Routledge via the DOI in this record.  This chapter outlines the methods to assess growth and maturation. Biological maturation varies with the biological system that is selected and comprises the assessment of sexual, morphological, dental, or skeletal maturation. The chapter describes how measures of physical fitness and performance are impacted by growth and maturation. It also outlines the methods used to examine body weight status and composition. The chapter examines laboratory-based testing protocols to determine and interpret aerobic and anaerobic fitness in children and adolescents. Although more commonly used in the research setting, laboratory-based measures of physical fitness in children and adolescents have typically focused on developing protocols to measure aerobic and anaerobic fitness. Three of the key parameters of aerobic fitness are: maximal oxygen uptake, blood lactate threshold, and oxygen cost of exercise. The chapter presents field-based testing batteries for measuring physical fitness in children and adolescents

Bone health in children and youth with Cystic Fibrosis: a systematic review and meta-analysis of matched cohort studies

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordObjective To assess the evidence regarding the differences in areal bone mineral density (aBMD) between children and adolescents with cystic fibrosis (CF) compared with their healthy peers, based on data from longitudinal studies. Study design We searched MEDLINE, SPORTDiscus, the Cochrane Library, PEDro (Physiotherapy Evidence Database), and Embase databases. Observational studies addressing the change of aBMD in children with CF and healthy children and adolescents were eligible. The DerSimonian and Laird method was used to compute pooled estimates of effect sizes (ES) and 95% CIs for the change of whole body (WB), lumbar spine (LS), and femoral neck (FN) aBMD. Results Six studies with participants with CF and 26 studies with healthy participants were included in the systematic review and meta-analysis. For the analysis in children with CF, the pooled ES for the change of WB aBMD was 0.29 (95% CI –0.15 to 0.74), for the change of LS aBMD was 0.13 (95% CI –0.16 to 0.41), and for the change of FN aBMD was 0.09 (95% CI –0.39 to 0.57). For the analysis in healthy children, the pooled ES for the change of WB aBMD was 0.37 (95% CI 0.26-0.49), for the change of LS aBMD was 0.13 (95% CI –0.16 to 0.41), and for the change of FN aBMD was 0.52 (95% CI 0.19-0.85). Conclusions aBMD development might not differ between children and adolescents with CF receiving medical care compared with their healthy peers. Further longitudinal studies in a CF population during growth and development are required to confirm our findings

The impact of sport participation on bone mass and geometry in adolescent males

Exercise is an effective approach for developing bone mass and adolescence is a key period to optimize bone health. However, sports specific training may have different effects on bone outcomes. This study examined the differences on bone outcomes between osteogenic (football) and non-osteogenic (swimming and cycling) sports and a control group in adolescent males. Methods: One hundred twenty one males (13.1±0.1 years) were measured: 41 swimmers, 37 footballers, 29 cyclists and 14 controls. Dual energy X-ray absorptiometry measured bone mineral density (BMD) and content (BMC) at lumbar spine, right and left hip and total body. Hip structural analysis evaluated bone geometry at the femoral neck. Quantitative ultrasound evaluated bone stiffness at both feet. Results: Footballers had significantly higher BMD at total body less head (7-9%), total hip (12-2%) and legs (7-11%) compared to all groups and significantly higher BMD at the femoral neck than controls (14%). Cyclists had higher BMD at the trochanter (10%) and BMC at the arms (10%) compared to controls. Geometrical analysis showed that footballers had significantly higher cross-sectional area (8-19%) compared to all groups, cross-sectional moment of inertia (17 %) compared to controls and section modulus compared to cyclists (11%) and controls (21%). Footballers had significantly higher bone stiffness compared to all groups (10-20%) at the dominant foot and (12-13%) at the nondominant foot compared to swimmers and controls. Conclusions: Adolescent male footballers exhibited higher bone density, geometry and stiffness compared to swimmers, cyclists and controls. Although swimmers and cyclists had higher bone outcomes compared to controls, these differences were not significant.The research leading to these results has received funding from the European Union Seventh Framework Programme ([FP7/2007-2013] under grant agreement n°. PCIG13-GA-2013-618496

Physical activity and bone health in schoolchildren: the mediating role of fitness and body fat

This is the final version of the article. Available from Public Library of Science via the DOI in this record.BACKGROUND: The relationship between physical activity (PA) and bone health is well known, although the role of percent body fat (%BF) and fitness as confounders or mediators in this relationship remains uncertain. OBJECTIVE: To examine whether the association between PA and bone mineral content (BMC) is mediated by %BF and cardiorespiratory fitness (CRF). METHODS: In this cross sectional study, BMC, total %BF (by DXA), vigorous PA (VPA), CRF, age and height were measured in 132 schoolchildren (62 boys, aged 8-11 years). ANCOVA was used to test differences in BMC by %BF, CRF and VPA, controlling for different sets of confounders. Simple mediation analyses and serial multiple mediation analyses were fitted to examine whether the relationship between PA and BMC is mediated by %BF and fitness. RESULTS: Children with high %BF had higher total body BMC than their peers after controlling for all sets of confounders. Children with good CRF or VPA had significantly less total body BMC after controlling for age and sex but in children with good CRF this inverse relation disappeared after adjusting by %BF. %BF and CRF both act as a full mediator in the association between VPA and BMC, after inclusion of the potential confounders in the models. CONCLUSION: Fitness and %BF seem to have a mediator role on the relationship between physical activity and bone mass.This study was funded by grant numbers PII1I09-0259-9898 and POII10-0208-5325 from the Ministry of Education and Science - Junta de Comunidades de Castilla-La Mancha, and Ministry of Health (FIS grant number PI081297). Additional funding was provided by the Research Network on Preventative Activities and Health Promotion (RD06/0018/0038)