ABSTRACT
The purpose of this descriptive cross-sectional study is to describe the amount and intensity of physical activity (PA) measured by accelerometry among adolescents participating in organized sports (SCP) and age-matched non-participating peers (NP). SCPs (332) and NPs (139) wore an accelerometer on the hip for seven days. PA was reported using the 1-min exponential moving average. The current moderate-to-vigorous physical activity (MVPA) recommendation of at least an average of 60â min of MVPA daily was reached by 85% of SCPs and 45% of NPs (p < .001). During training days, the MVPA times among SCPs ranged from 153 ± 39â min in males and 109 ± 35â min in females participating in basketball to 113 ± 33â min in males participating in floorball and 83 ± 32â min in females participating in gymnastics. Sports participation contributes rather strongly to the accumulation of the recommended amount of MVPA. During training days, SCPs, except for females participating in gymnastics, accumulated more MVPA than NPs. During non-training days, only males participating in cross-country skiing and females participating in track and field accumulated more MVPA than NPs.HIGHLIGHTSPA of Finnish adolescents participating in nine different organized sports and age-matched non-participating peers was measured by accelerometry for one week and the results are reported using the 1-min exponential moving average.Adolescents participating in many organized sports accumulated more PA than non-participants; this was observed in meeting the PA recommendations, total amount of PA at different intensities, and step count.The current PA recommendation of at least an average of 60â min of MVPA per day was reached by 85% of SCPs and 45% of non-participating peers. Vigorous physical activity at least three times per week was incorporated by 96% of SCPs and 81% of NPs.During training days, males participating in soccer, basketball, and cross-country skiing spent more time in MVPA than females participating in the same sports. During non-training days, the time spent in MVPA was similar between males and females participating in sports clubs.
Subject(s)
Basketball , Soccer , Male , Female , Humans , Adolescent , Infant, Newborn , Cross-Sectional Studies , Exercise , AccelerometryABSTRACT
BACKGROUND: Prospective studies investigating risk factors for low back pain (LBP) in youth athletes are limited. The aim of this prospective study was to investigate the association between hip-pelvic kinematics and vertical ground reaction force (vGRF) during landing tasks and LBP in youth floorball and basketball players. METHODS: Three-hundred-and-eighty-three Finnish youth female and male floorball and basketball players (mean age 15.7 ± 1.8) participated and were followed up on for 3 years. At the beginning of every study year the players were tested with a single-leg vertical drop jump (SLVDJ) and a vertical drop jump (VDJ). Hip-pelvic kinematics, measured as femur-pelvic angle (FPA) during SLVDJ landing, and peak vGRF and side-to-side asymmetry of vGRF during VDJ landing were the investigated risk factors. Individual exposure time and LBP resulting in time-loss were recorded during the follow-up. Cox's proportional hazard models with mixed effects and time-varying risk factors were used for analysis. RESULTS: We found an increase in the risk for LBP in players with decreased FPA during SLVDJ landing. There was a small increase in risk for LBP with a one-degree decrease in right leg FPA during SLVDJ landing (HR 1.09, 95% CI 1.02 to 1.17, per one-degree decrease of FPA). Our results showed no significant relationship between risk for LBP and left leg FPA (HR 1.04, 95% CI 0.97 to 1.11, per one-degree decrease of FPA), vGRF (HR 1.83, 95% CI 0.95 to 3.51) or vGRF side-to-side difference (HR 1.22, 95% CI 0.65 to 2.27) during landing tasks. CONCLUSIONS: Our results suggest that there is an association between hip-pelvic kinematics and future LBP. However, we did not find an association between LBP and vGRF. In the future, the association between hip-pelvic kinematics and LBP occurrence should be investigated further with cohort and intervention studies to verify the results from this investigation. LEVEL OF EVIDENCE: Prognosis, level 1b.
Subject(s)
Athletes , Basketball , Low Back Pain/epidemiology , Range of Motion, Articular , Adolescent , Biomechanical Phenomena , Female , Finland/epidemiology , Hip , Humans , Lower Extremity , Male , Pelvis , Proportional Hazards Models , Prospective StudiesABSTRACT
PURPOSE: Previous studies on paediatric and adolescent distal humeral fractures have reported an increase in surgical treatment activity. This increase could be hypothesized to reduce the incidence of corrective osteotomies. The aim of this study was to determine the incidence and trends of the primary surgical treatment of distal humeral fractures and corrective osteotomies in children and adolescents. METHODS: All Finns 18 years of age or younger who underwent treatment for distal humeral fracture between 1987 and 2016 were included in this population-based study. Surgical treatment data were obtained from the National Hospital Discharge Register of Finland. In calculating annual surgery incidence rates, the annual mid-year populations were obtained from the Official Statistics Finland. Surgical treatment was categorized into four groups; reposition and casting, osteosynthesis, external fixation and corrective osteotomy. RESULTS: During the 30-year study period, 9017 surgical procedures were performed in Finland with the primary or secondary diagnosis code being a distal humeral fracture. Of these, 6961 (77.2%) were osteosynthesis and the incidence of osteosynthesis (per 100 000 person-years) increased fourfold from 8.2 in 1987 to 34.1 in 2016. In the same 30-year study period, the total number of corrective osteotomies was low (151) with annual variation from one to 16. The incidence of corrective osteotomies (per 100 000 person-years) decreased sevenfold from 0.7 to 0.1. CONCLUSION: The incidence of surgical treatment with osteosynthesis in distal humeral fractures increased fourfold in Finland between 1987 and 2016. During the same time period, the number of corrective osteotomies diminished significantly. LEVEL OF EVIDENCE: IV.
ABSTRACT
Three hundred eighty-seven home-dwelling older women were divided into quartiles based on mean serum 25-hydroxyvitamin D (S-25(OH)D) levels. The rates of falls and fallers were about 40% lower in the highest S-25(OH)D quartile compared to the lowest despite no differences in physical functioning, suggesting that S-25(OH)D levels may modulate individual fall risk. INTRODUCTION: Vitamin D supplementation of 800 IU did not reduce falls in our previous 2-year vitamin D and exercise RCT in 70-80 year old women. Given large individual variation in individual responses, we assessed here effects of S-25(OH)D levels on fall incidence. METHODS: Irrespective of original group allocation, data from 387 women were explored in quartiles by mean S-25(OH)D levels over 6-24 months; means (SD) were 59.3 (7.2), 74.5 (3.3), 85.7 (3.5), and 105.3 (10.9) nmol/L. Falls were recorded monthly with diaries. Physical functioning and bone density were assessed annually. Negative binomial regression was used to assess incidence rate ratios (IRRs) for falls and Cox-regression to assess hazard ratios (HR) for fallers. Generalized linear models were used to test between-quartile differences in physical functioning and bone density with the lowest quartile as reference. RESULTS: There were 37% fewer falls in the highest quartile, while the two middle quartiles did not differ from reference. The respective IRRs (95% CI) for falls were 0.63 (0.44 to 0.90), 0.78 (0.55 to 1.10), and 0.87 (0.62 to 1.22), indicating lower falls incidence with increasing mean S-25(OH)D levels. There were 42% fewer fallers (HR 0.58; 040 to 0.83) in the highest quartile compared to reference. Physical functioning did not differ between quartiles. CONCLUSIONS: Falls and faller rates were about 40% lower in the highest S-25(OH)D quartile despite similar physical functioning in all quartiles. Prevalent S-25(OH)D levels may influence individual fall risk. Individual responses to vitamin D treatment should be considered in falls prevention.
Subject(s)
Accidental Falls/statistics & numerical data , Vitamin D/analogs & derivatives , Accidental Falls/prevention & control , Aged , Aged, 80 and over , Anthropometry/methods , Biomarkers/blood , Bone Density/drug effects , Bone Density/physiology , Cholecalciferol/therapeutic use , Dietary Supplements , Exercise Therapy/methods , Female , Finland/epidemiology , Humans , Incidence , Independent Living , Physical Functional Performance , Vitamin D/bloodABSTRACT
The aim of this study was to investigate the incidence of back pain in young basketball and floorball players under 21 years of age. The secondary aim was to examine risk factors especially for low back pain (LBP). Nine basketball and nine floorball teams (n = 396) participated in this prospective follow-up study (2011-2014). Young athletes (mean age 15.8 ± 1.9) performed physical tests and completed a questionnaire at baseline. The follow-up lasted 1-3 years per player. During the follow-up, back pain reported by the players was registered on a weekly basis and verified by a study physician. The exposure time (AE) on team practices and games was recorded by the coach. Altogether back pain was reported 61 times by 51 players. The incidence of back pain was 87 per 1000 athlete-years and 0.4 per 1000 hours of AE. Hamstrings, quadriceps and iliopsoas extensibility and general joint hypermobility were not associated with LBP. Furthermore, no association between LBP and leg extension strength or isometric hip abduction strength asymmetry was found in these young basketball and floorball players. In conclusion, back pain can lead to a considerable time-loss from training and competition among young basketball and floorball players and the pain tends to reoccur. Lower extremity muscle extensibility, general joint hypermobility or investigated lower extremity strength measures were not associated with the risk of LBP.
Subject(s)
Athletes , Basketball , Low Back Pain/epidemiology , Adolescent , Female , Finland , Follow-Up Studies , Humans , Incidence , Lower Extremity , Male , Muscle Strength , Prospective Studies , Range of Motion, Articular , Risk FactorsABSTRACT
This prospective study in youth football examined the relationship between frontal plane knee projection angle (FPKPA) during the single-leg squat and sustaining an acute lower extremity injury or acute non-contact lower extremity injury. Secondly, side-to-side asymmetry in FPKPA and sex as injury risk factors were explored. In addition, we investigated the influence of age, sex, and leg dominance on the FPKPA. A total of 558 youth football players (U11 to U14) participated in the single-leg squat test and prospective injury registration. FPKPA was not found as a risk factor for injuries at this age. There was no difference in the mean FPKPA between sexes. However, FPKPA was associated with age; oldest subjects displayed the smallest FPKPA. Among boys, the frontal plane knee control improved by age. Among girls, the relationship between age and FPKPA was not as clear, but the oldest girls displayed the smallest mean FPKPA in the study (12.2° ± 8.3°). The FPKPA was greater on the dominant kicking leg compared to the non-dominant support leg (P < .001 for boys, P = .001 for girls). However, side-to-side asymmetry in FPKPA was not associated with future injuries. In conclusion, frontal plane knee control in the single-leg squat was not associated with lower extremity injuries among young football players. As the single-leg squat to 90° knee flexion was too demanding for many subjects, easier single-leg squat test procedure or a different movement control test, such as a double-legged squat, could be more suitable for the young football players.
Subject(s)
Athletic Injuries/etiology , Knee/physiology , Lower Extremity/injuries , Soccer/injuries , Adolescent , Child , Female , Humans , Male , Prospective Studies , Range of Motion, Articular , Risk Factors , Youth Sports/injuriesABSTRACT
This prospective study investigated the incidence and pattern of acute time-loss injuries in young female and male basketball players. Eight basketball teams (n=201; mean age 14.85±1.5) participated in the follow-up study (2011-2014). The coaches recorded player participation in practices and games on a team diary. A study physician contacted the teams once a week to check new injuries and interviewed the injured players. In total, 158 injuries occurred. The overall rate of injury (per 1000 hours) was 2.64 (95% CI 2.23-3.05). Injury rate was 34.47 (95% CI 26.59-42.34) in basketball games and 1.51 (95% CI 1.19-1.82) in team practices. Incidence rate ratio (IRR) between game and practice was 22.87 (95% CI 16.71-31.29). Seventy-eight percent of the injuries affected the lower limbs. The ankle (48%) and knee (15%) were the most commonly injured body sites. The majority of injuries involved joint or ligaments (67%). Twenty-three percent of the injuries were severe causing more than 28 days absence from sports. Number of recurrent injuries was high (28% of all injuries), and most of them were ankle sprains (35 of 44, 79%). No significant differences were found in injury rates between females and males during games (IRR 0.88, 0.55, to 1.40) and practices (IRR 1.06, 0.69, to 1.62). In conclusion, ankle and knee ligament injuries were the most common injuries in this study. Moreover, the rate of recurrent ankle sprains was alarming.
Subject(s)
Ankle Injuries/epidemiology , Basketball/injuries , Adolescent , Female , Finland , Follow-Up Studies , Humans , Incidence , Knee Injuries/epidemiology , Male , Prospective Studies , Sprains and Strains/epidemiology , Youth SportsABSTRACT
UNLABELLED: This study assessed the cost-effectiveness of vitamin D supplementation and exercise, separately and combined, in preventing medically attended injurious falls among older home-dwelling Finnish women. Given a willingness to pay of 3,000 per injurious fall prevented, the exercise intervention had an 86 % probability of being cost-effective in this population. INTRODUCTION: The costs of falling in older persons are high, both to the individual and to society. Both vitamin D and exercise have been suggested to reduce the risk of falls. This study assessed the cost-effectiveness of vitamin D supplementation and exercise, separately and combined, in preventing medically attended injurious falls among older Finnish women. METHODS: Economic evaluation was based on the results of a previously published 2-year randomized controlled trial (RCT) where 409 community-dwelling women aged 70 to 80 years were recruited into four groups: (1) no exercise + placebo (D-Ex-), (2) no exercise + vitamin D 800 IU/day (D+Ex-), (3) exercise + placebo (D-Ex+), and (4) exercise + vitamin D 800 IU/day (D+Ex+). The outcomes were medically attended injurious falls and fall-related health care utilization costs over the intervention period, the latter evaluated from a societal perspective based on 2011 unit costs. Incremental cost-effectiveness ratios (ICER) were calculated for the number of injurious falls per person-year prevented and uncertainty estimated using bootstrapping. RESULTS: Incidence rate ratios (95 % CI) for medically attended injurious falls were lower in both Ex+ groups compared with D-Ex-: 0.46 (0.22 to 0.95) for D-Ex+, 0.38 (0.17 to 0.81) for D+Ex+. Step-wise calculation of ICERs resulted in exclusion of D+Ex- as more expensive and less effective. Recalculated ICERs were 221 for D-Ex-, 708 for D-Ex+, and 3,820 for D+Ex+; bootstrapping indicated 93 % probability that each injurious fall avoided by D-Ex+ per person year costs 708. At a willingness to pay 3,000 per injurious fall prevented, there was an 85.6 % chance of the exercise intervention being cost-effective in this population. CONCLUSIONS: Exercise was effective in reducing fall-related injuries among community-dwelling older women at a moderate cost. Vitamin D supplementation had marginal additional benefit. The results provide a firm basis for initiating feasible and cost-effective exercise interventions in this population.
Subject(s)
Accidental Falls/prevention & control , Bone Density Conservation Agents/administration & dosage , Dietary Supplements/economics , Exercise Therapy/economics , Vitamin D/administration & dosage , Wounds and Injuries/prevention & control , Accidental Falls/economics , Aged , Aged, 80 and over , Bone Density Conservation Agents/economics , Combined Modality Therapy , Cost-Benefit Analysis , Double-Blind Method , Exercise , Exercise Therapy/methods , Female , Health Care Costs/statistics & numerical data , Humans , Independent Living , Sensitivity and Specificity , Vitamin D/economics , Wounds and Injuries/economicsABSTRACT
Poor knee alignment is associated with increased loading of the joints, ligaments and tendons, and may increase the risk of injury. The study purpose was to compare differences in knee kinematics between basketball and floorball players during a vertical drop jump (VDJ) task. We wanted to investigate whether basketball players, whose sport includes frequent jump-landings, exhibited better knee control compared with floorball players, whose sport involves less jumping. Complete data was obtained from 173 basketball and 141 floorball players. Peak knee valgus and flexion angles during the VDJ were analyzed by 3D motion analysis.Larger knee valgus angles were observed among basketball players (- 3.2°, 95%CI -4.5 to - 2.0) compared with floorball players (- 0.9°, 95%CI -2.3 to 0.6) (P=0.022). Basketball players landed with a decreased peak knee flexion angle (83.1°, 95%CI 81.4 to 84.8) compared with floorball players (86.5°, 95%CI 84.6 to 88.4) (P=0.016). There were no significant differences in height, weight or BMI between basketball and floorball players. Female athletes exhibited significantly greater valgus angles than males. This study revealed that proper knee control during jump-landing does not seem to develop in young athletes simply by playing the sport, despite the fact that jump-landings occur frequently in practice and games.
Subject(s)
Basketball , Knee Joint/physiology , Range of Motion, Articular , Sports , Adolescent , Athletes , Biomechanical Phenomena , Child , Female , Humans , Knee Injuries/prevention & control , Male , Young AdultSubject(s)
Ankle Injuries/surgery , Ankle Joint/surgery , Ligaments, Articular/injuries , Practice Patterns, Physicians'/trends , Sprains and Strains/surgery , Evidence-Based Medicine , Finland , Humans , Ligaments, Articular/surgery , Practice Patterns, Physicians'/statistics & numerical data , Rupture/surgeryABSTRACT
UNLABELLED: This study showed that the prevalence of sarcopenia (low muscle mass and performance) among 70-80-year-old home-dwelling Finnish women is very low, while every third woman has WHO-based osteopenia (low bone mass). Muscle mass and derived indices of sarcopenia were not significantly related to measures of functional ability. INTRODUCTION: This study aims to determine the prevalence of sarcopenia and osteopenia among four hundred nine 70-80-year-old independently living Finnish women. The study compared consensus diagnostic criteria for age-related sarcopenia recently published by the European Working Group on Sarcopenia in Older People (EWGSOP) and the International Working Group on Sarcopenia (IWG) and assessed their associations with functional ability. METHODS: Femoral bone mineral density and body composition were measured with dual-energy X-ray absorptiometry. Skeletal muscle mass index (SMI), gait speed, and handgrip strength were used for sarcopenia diagnosis. Independent samples t tests determined group differences in body composition and functional ability according to recommended diagnostic cutpoints. Scatter plots were used to illustrate the correlations between the outcome measures used for diagnosis. RESULTS: Prevalence of sarcopenia was 0.9 and 2.7 % according to the EWGSOP and IWG, respectively. Thirty-six percent of the women had WHO-based osteopenia. Women with higher gait speed had significantly lower body weight and fat mass percentage, higher lean mass percentage, and better functional ability. Women with a low SMI weighed significantly less, with no significant differences in other outcome measures. SMI, gait speed, and grip strength were significantly correlated. CONCLUSIONS: Our study suggests that when using consensus definitions, sarcopenia is infrequent among older home-dwelling women while every third woman has osteopenia. In clinical practice, attention should be paid to the decline in functional ability rather than focusing on low muscle mass alone.
Subject(s)
Bone Diseases, Metabolic/epidemiology , Sarcopenia/epidemiology , Aged , Aged, 80 and over , Anthropometry/methods , Body Composition/physiology , Body Weight/physiology , Bone Density/physiology , Bone Diseases, Metabolic/physiopathology , Female , Femur/physiopathology , Finland/epidemiology , Gait/physiology , Hand Strength/physiology , Humans , Mass Screening/methods , Prevalence , Prospective Studies , Sarcopenia/diagnosis , Sarcopenia/physiopathologyABSTRACT
UNLABELLED: We determined the current trend in the number and incidence of hip fracture among persons 50 years of age or older in Finland between 1970 and 2010. After a clear rise until the late 1990s, the incidence of hip fracture has continuously declined. INTRODUCTION: Hip fractures are a major public health issue associated with excess morbidity and mortality. We determined the current trend in the number and incidence (per 100,000 persons) of hip fracture among older adults in Finland, an EU country with a well-defined Caucasian population of 5.4 million people. METHODS: We took into account all persons 50 years of age or older who were admitted to hospitals for primary treatment of hip fracture between 1970 and 2010. RESULTS: The number of hip fractures rose sharply till the end of 1990s (from 1,857 in 1970 to 7,122 in 1997), but since then, the rise has leveled off (7,594 fractures in 2010). Similarly, the age-adjusted incidence of hip fracture increased until 1997 but declined thereafter. The decline was especially clear in women whose age-adjusted incidence was 515.7 (per 100,000 persons) in 1997 but only 382.6 in 2010. In men, the corresponding incidence was 245.3 in 1997 and 210.7 in 2010. The number of hip fractures will increase 1.8-fold by 2030 even with the current 2010 incidence rates because the size of the 50-year-old or older population is likely to increase sharply in the near future. CONCLUSIONS: The declining trend in the incidence of hip fracture in Finland has continued through the entire first decade of the new millennium. Reasons for this development are uncertain, but possible explanations include increased average body weight, improved functional ability among elderly Finns, and specific measures to prevent bone loss and reduce the risk of falling.
Subject(s)
Hip Fractures/epidemiology , Osteoporotic Fractures/epidemiology , Age Distribution , Aged , Aged, 80 and over , Female , Finland/epidemiology , Humans , Incidence , Male , Middle Aged , Registries , Sex DistributionABSTRACT
INTRODUCTION: While hip protectors are effective in some clinical trials, many, including all in community settings, have been unable to demonstrate effectiveness. This is due partly to differences in the design and analysis. The aim of this report is to develop recommendations for subsequent clinical research. METHODS: In November of 2007, the International Hip Protector Research Group met to address barriers to the clinical effectiveness of hip protectors. This paper represents a consensus statement from the group on recommended methods for conducting future clinical trials of hip protectors. RESULTS AND CONCLUSIONS: Consensus recommendations include the following: the use of a hip protector that has undergone adequate biomechanical testing, the use of sham hip protectors, the conduct of clinical trials in populations with annual hip fracture incidence of at least 3%, a run-in period with demonstration of adequate adherence, surveillance of falls and adherence, and the inclusion of economic analyses. Larger and more costly clinical trials are required to definitively investigate effectiveness of hip protectors.
Subject(s)
Hip Fractures/prevention & control , Protective Devices , Randomized Controlled Trials as Topic/methods , Accidental Falls , Hip Fractures/etiology , Humans , Research Design , Treatment OutcomeABSTRACT
UNLABELLED: The association of long-term sport-specific exercise loading with cross-sectional geometry of the weight-bearing tibia was evaluated among 204 female athletes representing five different exercise loadings and 50 referents. All exercises involving ground impacts (e.g., endurance running, ball games, jumping) were associated with thicker cortex at the distal and diaphyseal sites of the tibia and also with large diaphyseal cross-section, whereas the high-magnitude (powerlifting) and non-impact (swimming) exercises were not. INTRODUCTION: Bones adapt to the specific loading to which they are habitually subjected. In this cross-sectional study, the association of long-term sport-specific exercise loading with the geometry of the weight-bearing tibia was evaluated among premenopausal female athletes representing 11 different sports. METHODS: A total of 204 athletes were divided into five exercise loading groups, and the respective peripheral quantitative computed tomographic data were compared to data obtained from 50 physically active, non-athletic referents. Analysis of covariance was used to estimate the between-group differences. RESULTS: At the distal tibia, the high-impact, odd-impact, and repetitive low-impact exercise loading groups had approximately 30% to 50% (p < 0.05) greater cortical area (CoA) than the referents. At the tibial shaft, these three impact groups had approximately 15% to 20% (p < 0.05) greater total area (ToA) and approximately 15% to 30% (p < 0.05) greater CoA. By contrast, both the high-magnitude and repetitive non-impact groups had similar ToA and CoA values to the reference group at both tibial sites. CONCLUSIONS: High-impact, odd-impact, and repetitive low-impact exercise loadings were associated with thicker cortex at the distal tibia. At the tibial shaft, impact loading was not only associated with thicker cortex, but also a larger cross-sectional area. High-magnitude exercise loading did not show such associations at either site but was comparable to repetitive non-impact loading and reference data. Collectively, the relevance of high strain rate together with moderate-to-high strain magnitude as major determinants of osteogenic loading of the weight-bearing tibia is implicated.
Subject(s)
Sports/physiology , Tibia/anatomy & histology , Adolescent , Adult , Anthropometry/methods , Bone Density/physiology , Diaphyses/anatomy & histology , Diaphyses/physiology , Female , Humans , Muscle, Skeletal/physiology , Tibia/diagnostic imaging , Tibia/physiology , Tomography, X-Ray Computed , Weight-Bearing/physiology , Young AdultABSTRACT
INTRODUCTION: Hip protectors represent a promising strategy for preventing fall-related hip fractures. However, clinical trials have yielded conflicting results due, in part, to lack of agreement on techniques for measuring and optimizing the biomechanical performance of hip protectors as a prerequisite to clinical trials. METHODS: In November 2007, the International Hip Protector Research Group met in Copenhagen to address barriers to the clinical effectiveness of hip protectors. This paper represents an evidence-based consensus statement from the group on recommended methods for evaluating the biomechanical performance of hip protectors. RESULTS AND CONCLUSIONS: The primary outcome of testing should be the percent reduction (compared with the unpadded condition) in peak value of the axial compressive force applied to the femoral neck during a simulated fall on the greater trochanter. To provide reasonable results, the test system should accurately simulate the pelvic anatomy, and the impact velocity (3.4 m/s), pelvic stiffness (acceptable range: 39-55 kN/m), and effective mass of the body (acceptable range: 22-33 kg) during impact. Given the current lack of clear evidence regarding the clinical efficacy of specific hip protectors, the primary value of biomechanical testing at present is to compare the protective value of different products, as opposed to rejecting or accepting specific devices for market use.
Subject(s)
Hip Fractures/prevention & control , Hip Joint , Materials Testing/methods , Protective Devices/standards , Accidental Falls , Equipment Design , Evidence-Based Medicine/methods , Hip Fractures/etiology , Humans , Research Design , Stress, MechanicalABSTRACT
OBJECTIVE: To investigate whether a 6-month neuromuscular warm-up programme could improve muscle power, balance, speed and agility. DESIGN: Cluster randomised controlled study. SETTING: 27 top level female floorball teams in Finland. PARTICIPANTS: 222 players (mean age 24 years); 119 in the intervention group and 103 in the control group were followed-up for one league season (6 months). INTERVENTION: A neuromuscular warm-up programme included sports-specific running technique, balance, jumping and strengthening exercises. The teams were advised to use the programme 1-3 times per week through the league season. One training session took approximately 25 min. MAIN OUTCOME MEASURES: Performance tests were assessed before and after the 6-month intervention and included static jump, countermovement jump, jumping over a bar, standing on a bar and figure-of-eight running. RESULTS: At 6 months, significant between-group differences were found in two outcome measures: jumping over a bar (number of jumps in 15 s) and standing on a bar (number of balance losses in 60 s). These differences were 2.3 jumps (95% CI 0.8 to 3.8, p = 0.003), favouring the intervention group, and -0.4 balance losses (95% CI -0.8 to 0.0, p = 0.050), again in favour of the intervention group. CONCLUSION: A neuromuscular warm-up programme improved the floorball players' sideways jumping speed and static balance. The exercises were also safe to perform and can thus be recommended for weekly training of floorball players. TRIAL REGISTRATION NUMBER: ISRCTN26550281.
Subject(s)
Exercise/physiology , Sports/physiology , Athletic Performance/physiology , Cluster Analysis , Female , Humans , Muscle Strength/physiology , Muscle Stretching Exercises , Muscle, Skeletal/physiology , Physical Endurance , Postural Balance , Running/physiology , Young AdultABSTRACT
Muscle performance, body composition and bone mass at the lumbar spine and proximal femur with DXA, structural traits at the tibia and radius with pQCT, and biomarkers of bone metabolism were assessed at baseline and after a three-month weight reduction in obese premenopausal women. Associations between changes in weight loss and bone traits were analyzed by linear regression analysis. The mean (SD) weight loss was 4.3 (4.5) kg ranging from 14.8 kg loss to 2.1 kg gain. Muscle performance was well maintained, while no signs of bone loss or structural deterioration were observed. Changes in bone resorption were significantly associated with weight change (for CTX, r=-0.34; p=0.043, and for TRACP5b, r=-0.35; p=0.032). There were borderline (p<0.1) negative correlations between changes in biomarkers and bone traits. Reduced fat mass was associated with slight mean increase in cortical density of the radial shaft. Also total body BMC increased slightly. Changes in both fat and lean mass were associated with a change in BMC. Our findings suggest that mild-to-moderate weight reduction modulated bone turnover slightly, but they do not support the common notion that such a weight reduction would compromise bone rigidity, possibly partly due to well maintained muscle performance.
Subject(s)
Bone Density/physiology , Bone and Bones/metabolism , Muscle Strength/physiology , Obesity/physiopathology , Weight Loss/physiology , Absorptiometry, Photon , Adult , Body Composition/physiology , Body Mass Index , Female , Humans , Muscle Strength Dynamometer , PremenopauseABSTRACT
SUMMARY: This study showed that about a half of the exercise-induced gain in dynamic balance and bone strength was maintained one year after cessation of the supervised high-intensity training of home-dwelling elderly women. However, to maintain exercise-induced gains in lower limb muscle force and physical functioning, continued training seems necessary. INTRODUCTION: Maintenance of exercise-induced benefits in physical functioning and bone structure was assessed one year after cessation of 12-month randomized controlled exercise intervention. METHODS: Originally 149 healthy women 70-78 years of age participated in the 12-month exercise RCT and 120 (81%) of them completed the follow-up study. Self-rated physical functioning, dynamic balance, leg extensor force, and bone structure were assessed. RESULTS: During the intervention, exercise increased dynamic balance by 7% in the combination resistance and balance-jumping training group (COMB). At the follow-up, a 4% (95% CI: 1-8%) gain compared with the controls was still seen, while the exercise-induced isometric leg extension force and self-rated physical functioning benefits had disappeared. During the intervention, at least twice a week trained COMB subjects obtained a significant 2% benefit in tibial shaft bone strength index compared to the controls. A half of this benefit seemed to be maintained at the follow-up. CONCLUSIONS: Exercise-induced benefits in dynamic balance and rigidity in the tibial shaft may partly be maintained one year after cessation of a supervised 12-month multi-component training in initially healthy elderly women. However, to maintain the achieved gains in muscle force and physical functioning, continued training seems necessary.