Showing papers in "Medicine and Science in Sports and Exercise in 2003"
TL;DR: Considering the diverse samples in this study, IPAQ has reasonable measurement properties for monitoring population levels of physical activity among 18- to 65-yr-old adults in diverse settings.
Abstract: CRAIG, C. L., A. L. MARSHALL, M. SJOSTROM, A. E. BAUMAN, M. L. BOOTH, B. E. AINSWORTH, M. PRATT, U. EKELUND, A. YNGVE, J. F. SALLIS, and P. OJA. International Physical Activity Questionnaire: 12-Country Reliability and Validity. Med. Sci. Sports Exerc., Vol. 35, No. 8, pp. 1381-1395, 2003. Background: Physical inactivity is a global concern, but diverse physical activity measures in use prevent international comparisons. The International Physical Activity Questionnaire (IPAQ) was developed as an instrument for cross-national monitoring of physical activity and inactivity. Methods: Between 1997 and 1998, an International Consensus Group developed four long and four short forms of the IPAQ instruments (administered by telephone interview or self-administration, with two alternate reference periods, either the "last 7 d" or a "usual week" of recalled physical activity). During 2000, 14 centers from 12 countries collected reliability and/or validity data on at least two of the eight IPAQ instruments. Test-retest repeatability was assessed within the same week. Concurrent (inter-method) validity was assessed at the same administration, and criterion IPAQ validity was assessed against the CSA (now MTI) accelerometer. Spearman's correlation coefficients are reported, based on the total reported physical activity. Results: Overall, the IPAQ questionnaires produced repeatable data (Spearman's clustered around 0.8), with comparable data from short and long forms. Criterion validity had a median of about 0.30, which was comparable to most other self-report validation studies. The "usual week" and "last 7 d" reference periods performed similarly, and the reliability of telephone administration was similar to the self-administered mode. Conclusions: The IPAQ instruments have acceptable measurement properties, at least as good as other established self-reports. Considering the diverse samples in this study, IPAQ has reasonable measurement properties for monitoring population levels of physical activity among 18- to 65-yr-old adults in diverse settings. The short IPAQ form "last 7 d recall" is recommended for national monitoring and the long form for research requiring more detailed assessment. Key Words: MEASUREMENT, SURVEILLANCE, EPIDEMIOLOGY
15,345 citations
TL;DR: The Yo-Yo intermittent recovery test was a valid measure of fitness performance in soccer and had a high reproducibility and sensitivity, allowing for detailed analysis of the physical capacity of athletes in intermittent sports.
Abstract: KRUSTRUP, P, M MOHR, T AMSTRUP, T RYSGAARD, J JOHANSEN, A STEENSBERG, P K PEDERSEN, and J BANGSBO The Yo-Yo Intermittent Recovery Test: Physiological Response, Reliability, and Validity Med Sci Sports Exerc, Vol 35, No 4, pp 697–705, 2003PurposeTo examine the physiological
1,175 citations
TL;DR: The absence of dynamic knee joint stability may be responsible for increased rates of knee injury in females but is not normally measured in athletes before participation, no method for accurate and practical screening and identification of athletes at increased risk of ACL injury is currently available.
Abstract: FORD, K. R., G. D. MYER, and T. E. HEWETT. Valgus Knee Motion during Landing in High School Female and Male Basketball Players. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1745–1750, 2003. Purpose: The purpose of this study was to utilize three-dimensional kinematic (motion) analysis to determine whether gender differences existed in knee valgus kinematics in high school basketball athletes when performing a landing maneuver. The hypothesis of this study was that female athletes would demonstrate greater valgus knee motion (ligament dominance) and greater side-to-side (leg dominance) differences in valgus knee angle at landing. These differences in valgus knee motion may be indicative of decreased dynamic knee joint control in female athletes. Methods: Eighty-one high school basketball players, 47 female and 34 male, volunteered to participate in this study. Valgus knee motion and varus-valgus angles during a drop vertical jump (DVJ) were calculated for each subject. The DVJ maneuver consisted of dropping off of a box, landing and immediately performing a maximum vertical jump. The first landing phase was used for the analysis. Results: Female athletes landed with greater total valgus knee motion and a greater maximum valgus knee angle than male athletes. Female athletes had significant differences between their dominant and nondominant side in maximum valgus knee angle. Conclusion: The absence of dynamic knee joint stability may be responsible for increased rates of knee injury in females but is not normally measured in athletes before participation. No method for accurate and practical screening and identification of athletes at increased risk of ACL injury is currently available to target those individuals that would benefit from neuromuscular training before sports participation. Prevention of female ACL injury from five times to equal the rate of males would allow tens of thousands of young females to avoid the potentially devastating effects of ACL injury on their athletic careers. Key Words: ACL INJURY, NEUROMUSCULAR CONTROL, MUSCULAR IMBALANCE, INJURY PREVENTION, GENDER DIFFERENCES, PREPARTICIPATION SCREENING
956 citations
TL;DR: In general, pedometers are most accurate for assessing steps, less accurate for assessing distance, and even less accurately for assessing kilocalories.
Abstract: CROUTER, S. E., P. L. SCHNEIDER, M. KARABULUT, and D. R. BASSETT, JR. Validity of 10 Electronic Pedometers for Measuring Steps, Distance, and Energy Cost. Med. Sci. Sports Exerc., Vol. 35, No. 8, pp. 1455–1460, 2003.PurposeThis study examined the effects of walking speed on the accuracy and
927 citations
TL;DR: WBV, and the reflexive muscle contraction it provokes, has the potential to induce strength gain in knee extensors of previously untrained females to the same extent as resistance training at moderate intensity.
Abstract: DELECLUSE, C., M. ROELANTS, and S. VERSCHUEREN. Strength Increase after Whole-Body Vibration Compared with Resistance Training. Med. Sci. Sports Exerc., Vol. 35, No. 6, pp. 1033–1041, 2003. Purpose: The aim of this study was to investigate and to compare the effect of a 12-wk period of whole-body vibration training and resistance training on human knee-extensor strength. Methods: Sixty-seven untrained females (21.4 1.8 yr) participated in the study. The whole-body vibration group (WBV, N 18) and the placebo group (PL, N 19) performed static and dynamic knee-extensor exercises on a vibration platform. The acceleration of the vibration platform was between 2.28 g and 5.09 g, whereas only 0.4 g for the PL condition. Vibration (35– 40 Hz) resulted in increased EMG activity, but the EMG signal remained unchanged in the PL condition. The resistance-training group (RES, N 18) trained knee extensors by dynamic leg-press and leg-extension exercises (10 –20 RM). All training groups exercised 3 wk 1 . The control group (CO, N 12) did not participate in any training. Pre- and postisometric, dynamic, and ballistic knee-extensor strength were measured by means of a motor-driven dynamometer. Explosive strength was determined by means of a counter-movement jump. Results: Isometric and dynamic knee-extensor strength increased significantly (P 0.001) in both the WBV group (16.6 10.8%; 9.0 3.2%) and the RES group (14.4 5.3%; 7.0 6.2%), respectively, whereas the PL and CO group showed no significant (P 0.05) increase. Counter-movement jump height enhanced significantly (P 0.001) in the WBV group (7.6 4.3%) only. There was no effect of any of the interventions on maximal speed of movement, as measured by means of ballistic tests. Conclusions: WBV, and the reflexive muscle contraction it provokes, has the potential to induce strength gain in knee extensors of previously untrained females to the same extent as resistance training at moderate intensity. It was clearly shown that strength increases after WBV training are not attributable to a placebo effect. Key Words: MUSCLE STRENGTH, TONIC VIBRATION REFLEX, COUNTER-MOVEMENT JUMP, STRENGTH TRAINING
754 citations
TL;DR: This review presents the 2002 update of the human gene map for physical performance and health-related phenotypes, based on peer-reviewed papers published by the end of 2002 and includes association studies with candidate genes, genome-wide scans with polymorphic markers, and single gene defects causing exercise intolerance to variable degrees.
Abstract: The current review presents the 2005 update of the human gene map for physical performance and health-related fitness phenotypes. It is based on peer-reviewed papers published by the end of 2005. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise, or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed, but a gene or locus must be supported by at least one positive study before being inserted on the map. By the end of 2000, in the early version of the gene map, 29 loci were depicted. In contrast, the 2005 human gene map for physical performance and health-related phenotypes includes 165 autosomal gene entries and QTL, plus five others on the X chromosome. Moreover, there are 17 mitochondrial genes in which sequence variants have been shown to influence relevant fitness and performance phenotypes. Thus, the map is growing in complexity. Unfortunately, progress is slow in the field of genetics of fitness and performance, primarily because the number of laboratories and scientists focused on the role of genes and sequence variations in exercise-related traits continues to be quite limited.
750 citations
TL;DR: It is important for researchers who use pedometers to assess physical activity to be aware of their accuracy and reliability, due to the variation that exists among models in regard to the internal mechanism and sensitivity.
Abstract: SCHNEIDER, P. L., S. E. CROUTER, O. LUKAJIC, and D. R. BASSETT, JR. Accuracy and Reliability of 10 Pedometers for Measuring Steps over a 400-m Walk. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1779–1784, 2003.PurposeThe purpose of this study was to determine the accuracy and reliability of
659 citations
TL;DR: Findings provided concurrent validation of the OMNI-RES to measure RPE for the active muscle and overall body in young recreationally trained female and male weight lifters performing upper- and lower-body resistance exercise.
Abstract: ROBERTSON, R. J., F. L. GOSS, J. RUTKOWSKI, B. LENZ, C. DIXON, J. TIMMER, K. FRAZEE, J. DUBE, and J. ANDREACCI. Concurrent Validation of the OMNI Perceived Exertion Scale for Resistance Exercise. Med. Sci. Sports Exerc., Vol. 35, No. 2, pp. 333–341, 2003.PurposeConcurrent validity of the newly devel
631 citations
TL;DR: The dose-response trends identified in this analysis support the theory of progression in resistance program design and can be useful in the development of training programs designed to optimize the effort to benefit ratio.
Abstract: RHEA, M. R., B. A. ALVAR, L. N. BURKETT, and S. D. BALL. A Meta-Analysis to Determine the Dose Response for Strength Development. Med. Sci. Sports Exerc., Vol. 35, No. 3, pp. 456–464, 2003.PurposeThe identification of a quantifiable dose-response relationship for strength training is importa
614 citations
TL;DR: The prevalence of physical inactivity in this Brazilian adult population is high, even though lower than reported in studies of leisure-time activity alone in other populations, and studies in developing countries may be seriously biased if activities during labor, transportation, and housework are not assessed.
Abstract: HALLAL, P C, C G VICTORA, J C K WELLS, and R C LIMA Physical Inactivity: Prevalence and Associated Variables in Brazilian Adults Med Sci Sports Exerc, Vol 35, No 11, pp 1894–1900, 2003PurposeTo measure the prevalence of physical inactivity, and variables associated with it,
584 citations
TL;DR: The physical activity scale appears to be a simple and valid alternative to measuring physical activity by diary in adult sedentary to moderately active Danes and it provides detailed information on different activity levels as a single measure of the total amount of physical activity on an average weekday.
Abstract: AADAHL, M., and T. JORGENSEN. Validation of a New Self-Report Instrument for Measuring Physical Activity. Med. Sci. Sports Exerc., Vol. 35, No. 7, pp. 1196–1202, 2003.PurposeDevelopment and validation of a physical activity scale for measuring physical activity in 24 h of sports, work, and l
TL;DR: Physical activity is associated with lower risk of developing certain site-specific cancers, in particular colon and breast cancers.
Abstract: Purpose The aim of this paper is to examine whether physical activity plays any role in the prevention of cancer. Methods To accomplish this, data from published epidemiologic studies on the relation between physical activity and the risk of developing cancer were reviewed. Results The data are clear in showing that physically active men and women have about a 30-40% reduction in the risk of developing colon cancer, compared with inactive persons. Although the data are sparse, it appears that 30-60 min.d(-1) of moderate- to vigorous-intensity physical activity is needed to decrease risk. There is a dose-response relation, with risk declining further at higher levels of physical activity. It is also clear that physical activity is not associated with the risk of developing rectal cancer. With regard to breast cancer, there is reasonably clear evidence that physically active women have about a 20-30% reduction in risk, compared with inactive women. It also appears that 30-60 min.d(-1) of moderate- to vigorous-intensity physical activity is needed to decrease the risk of breast cancer, and that there is likely a dose-response relation. For prostate cancer, the data are inconsistent regarding whether physical activity plays any role in the prevention of this cancer. There are relatively few studies on physical activity and lung cancer prevention. The available data suggest that physically active individuals have a lower risk of lung cancer; however, it is difficult to completely account for cigarette smoking. There is little information on the role of physical activity in preventing other cancers. Conclusion Physical activity is associated with lower risk of developing certain site-specific cancers, in particular colon and breast cancers.
TL;DR: Measurement of VO(2max) in sedentary men with risk factors may provide an efficient means for targeting individuals who would benefit from interventions to prevent the MS and its consequences.
Abstract: LAKKA, T A, D E LAAKSONEN, H-M LAKKA, N MANNIKKO, L K NISKANEN, R RAURAMAA, and J T SALONEN Sedentary Lifestyle, Poor Cardiorespiratory Fitness, and the Metabolic Syndrome Med Sci Sports Exerc, Vol 35, No 8, pp 1279–1286, 2003PurposeThe cross-sectional associations of le
TL;DR: The positive contribution that parents can have on activity practices of their young daughters is indicated, and links between activity-related parenting strategies and girls' physical activity patterns are examined.
Abstract: Purpose
Using a sample of 180 9-yr-old girls and their parents, this study examined (a) parents’ activity-related parenting strategies and similarities and differences in such strategies for mothers and fathers, and (b) links between activity-related parenting strategies and girls’ physical activity patterns.
TL;DR: Preliminary research suggests that exercise may be an effective intervention for enhancing quality of life (QOL) in cancer survivors as well as during and after cancer treatment.
Abstract: Purpose: To provide an overview of research that has examined exercise in cancer survivors including recently completed trials at the University of Alberta. Methods: A search of published studies using electronic data bases and previous review articles. The review is divided into breast and nonbreast cancers, during and after treatment, and trials from the University of Alberta. Results: Forty-seven published studies were located and summarized plus four trials from the University of Alberta. Almost all studies showed beneficial effects of exercise in breast and nonbreast cancer groups alike as well as during and after cancer treatment. Conclusion: Preliminary research suggests that exercise may be an effective intervention for enhancing quality of life (QOL) in cancer survivors. The effects of exercise on biomarkers, cancer recurrence, other diseases, and overall survival are unknown. Future research is needed to extend our knowledge beyond breast cancer survivors, conduct second generation studies in breast cancer survivors, examine mechanisms for changes in QOL, compare exercise with other QOL interventions, and examine biomarkers, cancer recurrence, and survival.
TL;DR: Aerobic exercise training in patients with the metabolic syndrome can be useful as a treatment strategy and provides support for a role for physical activity in the prevention of chronic disease.
Abstract: KATZMARZYK, P. T., A. S. LEON, J. H. WILMORE, J. S. SKINNER, D. C. RAO, T. RANKINEN, and C. BOUCHARD. Targeting the Metabolic Syndrome with Exercise: Evidence from the HERITAGE Family Study. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1703–1709, 2003. Purpose: To determine the efficacy of exercise training in treating the metabolic syndrome. Methods: The sample included 621 black and white participants from the HERITAGE Family Study, identified as sedentary and apparently healthy (no chronic disease or injury). The metabolic syndrome was defined as having three or more risk factors according to the guidelines of the National Cholesterol Education Program, including elevated waist circumference, blood pressure, triglycerides, blood glucose, and low HDL cholesterol. The presence of the metabolic syndrome and component risk factors were determined before and after 20 wk of supervised aerobic exercise training. Results: The prevalence of the metabolic syndrome was 16.9% in this sample (105/621) of apparently healthy participants. Of the 105 participants with the metabolic syndrome at baseline, 30.5% (32 participants) were no longer classified as having the metabolic syndrome after the exercise training. Among the 32 participants who improved their metabolic profile, 43% decreased triglycerides, 16% improved HDL cholesterol, 38% decreased blood pressure, 9% improved fasting plasma glucose, and 28% decreased their waist circumference. There were no sex or race differences in the efficacy of exercise in treating the metabolic syndrome: 32.7% of men, 28.0% of women, 29.7% of black, and 30.9% of white participants with the metabolic syndrome were no longer classified as having the syndrome after training. Conclusion: Aerobic exercise training in patients with the metabolic syndrome can be useful as a treatment strategy and provides support for a role for physical activity in the prevention of chronic disease.
TL;DR: The epidemiology of walking for physical activity among respondents to the U.S. Physical Activity Study is described to identify important information that can be used to help guide future interventions that promote walking as a form of physical activity.
Abstract: EYLER, A. A., R. C. BROWNSON, S. J. BACAK, and R. A. HOUSEMANN. The Epidemiology of Walking for Physical Activity in the United States. Med. Sci. Sports Exerc., Vol. 35, No. 9, pp. 1529–1536, 2003.PurposeThe purpose of this paper was to describe the epidemiology of walking for physical activ
TL;DR: CSA accelerometers erroneously detect more nonsteps than the Yamax pedometer under typical motor vehicle traveling conditions and this threat to validity is likely only problematic when using the accelerometer to assess physical activity in sedentary individuals who travel extensively by motor vehicle.
Abstract: LE MASURIER, G. C., and C. TUDOR-LOCKE. Comparison of Pedometer and Accelerometer Accuracy under Controlled Conditions. Med. Sci. Sports Exerc., Vol. 35, No. 5, pp. 867–871, 2003.Purpose:The purpose of this investigation was to compare the concurrent accuracy of the CSA accelerometer and the
TL;DR: In PP conditions, activation patterns appear to be selected to support the external loads experienced at the knee, e.g., medial muscles activated to resist applied valgus moments, have implications for the etiology of noncontact knee ligament injuries.
Abstract: BESIER, T. F., D. G. LLOYD, and T. R. ACKLAND. Muscle Activation Strategies at the Knee during Running and Cutting Maneuvers. Med. Sci. Sports Exerc., Vol. 35, No. 1, pp. 119–127, 2003.PurposeThe purpose of this article was to investigate the activation patterns of muscles surrounding the kn
TL;DR: Evaluating the reliability and validity of the CSA in a wide walking-running speed range in laboratory and field found between-subject reliability was related to step frequency, presumably due to relatively constant vertical acceleration in running.
Abstract: BRAGE, S., N. WEDDERKOPP, P. W. FRANKS, L. B. ANDERSEN, and K. FROBERG. Reexamination of Validity and Reliability of the CSA Monitor in Walking and Running. Med. Sci. Sports Exerc., Vol. 35, No. 8, pp. 1447–1454, 2003.PurposeTo evaluate the reliability and validity of the CSA (model 7164) ac
TL;DR: Although many cytokines recruiting and priming neutrophils and monocytes were secreted and functional after exhaustive exercise, overwhelming antioxidant and antiinflammatory defenses were induced, preventing exercise-induced oxidative stress.
Abstract: SUZUKI, K., S. NAKAJI, M. YAMADA, Q. LIU, S. KURAKAKE, N. OKAMURA, T. KUMAE, T. UMEDA, and K. SUGAWARA. Impact of a Competitive Marathon Race on Systemic Cytokine and Neutrophil Responses. Med. Sci. Sports Exerc., Vol. 35, No. 2, pp. 348–355, 2003.PurposeTo investigate whether cytokines and neutroph
TL;DR: The findings indicate that the combined effect on net muscle protein synthesis of carbohydrate and amino acids given together after resistance exercise is roughly equivalent to the sum of the independent effects of either given alone.
Abstract: MILLER, S. L., K. D. TIPTON, D. L. CHINKES, S. E. WOLF, and R. R. WOLFE. Independent and Combined Effects of Amino Acids and Glucose after Resistance Exercise. Med. Sci. Sports Exerc., Vol. 35, No. 3, pp. 449–455, 2003.PurposeThis study was designed to assess the independent and combined eff
TL;DR: In healthy elderly subjects, the 6-MWT represents a submaximal exercise, but at almost 80% of the VO2(max), so to be exploitable, two familiarization attempts are required to limit the learning effect.
Abstract: KERVIO, G, F CARRE, and N S VILLE Reliability and Intensity of the Six-Minute Walk Test in Healthy Elderly Subjects Med Sci Sports Exerc, Vol 35, No 1, pp 169–174, 2003PurposeThe 6-min walk test (6-MWT) is an easy and validated field test, generally used in patients to assess th
TL;DR: The number of sets functions up to a point as a stimulus for increased hormonal concentrations in order to optimize adaptations with MH and SE protocols, and has no effect on a MS protocol.
Abstract: SMILIOS, I., T. PILIANIDIS, M. KARAMOUZIS, and S. P. TOKMAKIDIS. Hormonal Responses after Various Resistance Exercise Protocols. Med. Sci. Sports Exerc., Vol. 35, No. 4, pp. 644 – 654, 2003. Purpose: This study examined the effects of the number of sets on testosterone, cortisol, and growth hormone (hGH) responses after maximum strength (MS), muscular hypertrophy (MH), and strength endurance (SE) protocols. Methods: Eleven young men performed multi-joint dynamic exercises using MS (5 reps at 88% of one-repetition maximum (1-RM), 3-min rest) and MH (10 reps at 75% of 1-RM, 2-min rest) protocols with 2, 4, and 6 sets at each exercise; and an SE (15 reps at 60% of 1-RM, 1-min rest) with 2 and 4 sets. Hormonal concentrations were measured before exercise, immediately after, and at 15 and 30 min of recovery. Results: The number of sets did not affect the hormonal responses after the MS protocol. Cortisol and hGH were higher (P 0.05) after the four-set compared with the two-set sessions in the MH and SE protocols. No differences were observed between the six-set and the four-set sessions in the MH protocol. Cortisol and hGH were higher (P 0.05) than the MS after the SE and MH protocols, and only when four and six sets were performed in the latter. hGH was higher than the MH after the SE protocol, whether two or four sets were executed, whereas cortisol (P 0.05) was higher after the SE protocol only when two sets were performed. Testosterone did not change with any workout. Conclusion: The number of sets functions up to a point as a stimulus for increased hormonal concentrations in order to optimize adaptations with MH and SE protocols, and has no effect on a MS protocol. Furthermore, the number of sets may differentiate long-term adaptations with MS, MH, and SE protocols causing distinct hormonal responses. Key Words: STRENGTH, HYPERTROPHY, STRENGTH ENDURANCE, NUMBER OF SETS, TOTAL WORK
TL;DR: The present data indicate that transcriptional events largely contribute to increases in mitochondrial mass in human skeletal muscle with endurance training.
Abstract: Mitochondria in skeletal muscle tissue can undergo rapid and characteristic changes as a consequence of manipulations of muscle use and environmental conditions. Endurance exercise training leads to increases of mitochondrial volume of up to 50% in training interventions of a few weeks in previously untrained subjects. Additionally, a shift of substrate metabolism toward a higher reliance on lipids is observed, structurally reflected as a doubling of the intramyocellular lipid content. A similar increase in intramyocellular lipids without an increase in mitochondrial volume is observed as a consequence of a high-fat diet. Strength training has a major impact on muscle myofibrillar volume, however the mitochondrial compartment appears relatively unchanged. Bedrest and microgravity conditions lead to losses of both myofibrillar and mitochondrial volume, likely as a consequence of the decrease in metabolic and mechanical stress on muscle tissue. Permanent severe hypoxia leads to a loss of muscle mass and muscle oxidative capacity; however, hypoxia signaling events are triggered, which lead to distinct reprogramming phenomena of the transcriptome of the muscle cells. The molecular mechanisms that orchestrate the plasticity of skeletal muscle mitochondria are just beginning to unfold. The present data indicate that transcriptional events largely contribute to increases in mitochondrial mass in human skeletal muscle with endurance training. Expression of mitochondrial proteins from the nuclear and mitochondrial genomes is coordinated and involves the nuclear-encoded transcription factors NRF-1 and TFAM. Transcription of genes encoding the mitochondrial proteins involved in beta oxidation can be regulated separately from the genes of the Krebs cycle and the respiratory chain. Transcription factors AP-1 and PPARalpha/gamma and the protein kinase AMPK are signaling molecules that transduce the metabolic and mechanical factors sensed during endurance training into the complex transcriptional adaptations of mitochondrial proteins.
TL;DR: Examination of the relationships between disordered eating, menstrual irregularity, and low bone mineral density (BMD) in young competitive female distance runners concluded that disorderedeating is strongly related to menstrual irregularness, menstruation irregularity is associated with low BMD, and disordered Eating is associatedwith low B MD in the absence of menstrual irregularities.
Abstract: COBB, K. L., L. K. BACHRACH, G. GREENDALE, R. MARCUS, R. M. NEER, J. NIEVES, M. F. SOWERS, B. W. BROWN, JR., G. GOPALAKRISHNAN, C. LUETTERS, H. K. TANNER, B. WARD, and J. L. KELSEY. Disordered Eating, Menstrual Irregularity, and Bone Mineral Density in Female Runners. Med. Sci. Sports Exerc., Vol. 35, No. 5, pp. 711–719, 2003. Purpose: To examine the relationships between disordered eating, menstrual irregularity, and low bone mineral density (BMD) in young female runners. Methods: Subjects were 91 competitive female distance runners aged 18 –26 yr. Disordered eating was measured by the Eating Disorder Inventory (EDI). Menstrual irregularity was defined as oligo/amenorrhea (0 –9 menses per year). BMD was measured by dual x-ray absorptiometry. Results: An elevated score on the EDI (highest quartile) was associated with oligo/amenorrhea, after adjusting for percent body fat, age, miles run per week, age at menarche, and dietary fat, (OR [95% CI]: 4.6 [1.1–18.6]). Oligo/amenorrheic runners had lower BMD than eumenorrheic runners at the spine (5%), hip (6%), and whole body (3%), even after accounting for weight, percent body fat, EDI score, and age at menarche. Eumenorrheic runners with elevated EDI scores had lower BMD than eumenorrheic runners with normal EDI scores at the spine (11%), with trends at the hip (5%), and whole body (5%), after adjusting for differences in weight and percent body fat. Runners with both an elevated EDI score and oligo/amenorrhea had no further reduction in BMD than runners with only one of these risk factors. Conclusion: In young competitive female distance runners, (i) disordered eating is strongly related to menstrual irregularity, (ii) menstrual irregularity is associated with low BMD, and (iii) disordered eating is associated with low BMD in the absence of menstrual irregularity. Key Words: FEMALE ATHLETES, LONG DISTANCE, OSTEOPENIA, OSTEOPOROSIS, AMENORRHEA, OLIGOMENORRHEA, EATING ATTITUDES, EATING DISORDER INVENTORY, FEMALE ATHLETE TRIAD
TL;DR: Significant muscle size and architectural adaptations can occur in concurrently training athletes in response to a 5-wk training program, possibly associated with the force and velocity characteristics of the training exercises but not the movement patterns.
Abstract: BLAZEVICH, A. J., N. D. GILL, R. BRONKS, and R. U. NEWTON. Training-Specific Muscle Architecture Adaptation after 5-wk Training in Athletes. Med. Sci. Sports Exerc., Vol. 35, No. 12, pp. 2013–2022, 2003.PurposeThis study examined changes in the muscle size, muscle architecture, strength, and
TL;DR: The taper is a progressive nonlinear reduction of the training load during a variable period of time, in an attempt to reduce the physiological and psychological stress of daily training and optimize sports performance.
Abstract: The taper is a progressive nonlinear reduction of the training load during a variable period of time, in an attempt to reduce the physiological and psychological stress of daily training and optimize sports performance. The aim of the taper should be to minimize accumulated fatigue without compromising adaptations. This is best achieved by maintaining training intensity, reducing the training volume (up to 60-90%) and slightly reducing training frequency (no more than 20%). The optimal duration of the taper ranges between 4 and more than 28 d. Progressive nonlinear tapers are more beneficial to performance than step tapers. Performance usually improves by about 3% (usual range 0.5-6.0%), due to positive changes in the cardiorespiratory, metabolic, hematological, hormonal, neuromuscular, and psychological status of the athletes.
TL;DR: This case report describes a new application of this therapy in the arthroscopic treatment of a large, nontraumatic avulsion of articular cartilage in the knee of an adolescent soccer player, allowing a rapid resumption of symptom-free athletic activity.
Abstract: SANCHEZ, M., J. AZOFRA, E. ANITUA, I. ANDIA, S. PADILLA, J. SANTISTEBAN, and I. MUJIKA. Plasma Rich in Growth Factors to Treat an Articular Cartilage Avulsion: A Case Report. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1648 -1652, 2003. Introduction: The application of an autologous plasma rich in growth factors is beneficial in restoring connective tissues, as shown by clinical evidence in oral surgery and more recently in arthroscopic anterior cruciate ligament reconstruction and two cases of ruptured Achilles tendon in professional athletes. This is attributed to the slow delivery of growth factors from harvested platelets that have been activated by endogenous thrombin promoted by the addition of calcium chloride. Purpose: This case report describes a new application of this therapy in the arthroscopic treatment of a large, nontraumatic avulsion of articular cartilage in the knee of an adolescent soccer player. Methods: After arthroscopic reattachment of the large (2 cm) loose chondral body in its crater in the medial femoral condyle, autologous plasma rich in growth factors was injected into the area between the crater and the fixed fragment. Results and Conclusion: Despite the extremely poor prognosis of the case, complete articular cartilage healing was considerably accelerated, and the functional outcome was excellent, allowing