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A 5-year prospective study on the time course of women's gymnastics injuries was conducted on a successful NCAA Division I team. Gymnasts recorded injuries on a computer terminal or via computer dot sheets immediately before each training session, including the injured body part, the event or activity, and the date of the injury. The definition of injury was 'any damaged body part that would interfere with training.' Athletes recorded injuries on the 1st day of onset and subsequently until the injury was healed. The initial onset of injury was considered a new injury. Subsequent records of the injury were considered continuing injury. Thirty-seven athletes participated through five collegiate seasons. They accounted for 5602 total training exposures with an average of 151.4 exposures per athlete. The analyses showed that gymnasts trained with an injury approximately 71% of the exposures, and a new injury could be expected from a gymnast during approximately 9% of the exposures. The largest number of injuries were of the repetitive stress syndrome type. The time series information showed that total injuries tended to increase until the middle of the competitive season, while new injuries showed prominent increases during specific training periods and during competition preparation and performance. [ABSTRACT FROM AUTHOR]

A popular algorithm to predict VO2Peak from the one-mile run/walk test (1MRW) includes body mass index (BMI), which manifests practical issues in school settings. The purpose of this study was to develop an aerobic capacity model from 1MRW in adolescents independent of BMI. Cardiorespiratory endurance data were collected on 90 adolescents aged 13-16 years. The 1MRW was administered on an outside track and a laboratory VO2Peak test was conducted using a maximal treadmill protocol. Multiple linear regression was employed to develop the prediction model. Results yielded the following algorithm: VO2Peak = 7.34 × (1MRW speed in m s(-1)) + 0.23 × (age × sex) + 17.75. The New Model displayed a multiple correlation and prediction error of R = 0.81, standard error of the estimate = 4.78 ml kg(-1) · min(-1), with measured VO2Peak and good criterion-referenced (CR) agreement into FITNESSGRAM's Healthy Fitness Zone (Kappa = 0.62; percentage agreement = 84.4%; Φ = 0.62). The New Model was validated using k-fold cross-validation and showed homoscedastic residuals across the range of predicted scores. The omission of BMI did not compromise accuracy of the model. In conclusion, the New Model displayed good predictive accuracy and good CR agreement with measured VO2Peak in adolescents aged 13-16 years.

Context: Chronic exertional compartment syndrome (CECS) is a debilitating condition resulting in loss of function and a decrease in athletic performance. Cases of CECS are increasing among Nordic skiers; therefore, analysis of intracompartmental pressures (ICPs) before and after Nordic skiing is warranted., Objective: To determine if lower leg anterior and lateral ICPs and subjective lower leg pain levels increased after a 20-minute Nordic rollerskiing time trial and to examine if differences existed between postexercise ICPs for the 2 Nordic rollerskiing techniques, classic and skate., Design: Crossover study., Setting: Outdoor paved loop., Patients or Other Participants: Seven healthy Division I Nordic skiers (3 men, 4 women; age = 22.71 ± 1.38 y, height = 175.36 ± 6.33 cm, mass = 70.71 ± 6.58 kg)., Intervention(s): Participants completed two 20-minute rollerskiing time trials using the classic and skate technique in random order. The time trials were completed 7 days apart. Anterior and lateral ICPs and lower leg pain scores were obtained at baseline and at minutes 1 and 5 after rollerskiing., Main Outcome Measure(s): Anterior and lateral ICPs (mm Hg) were measured using a Stryker Quic STIC handheld monitor. Subjective measures of lower leg pain were recorded using the 11-point Numeric Rating Scale., Results: Increases in both anterior (P = .000) and lateral compartment (P = .002) ICPs were observed, regardless of rollerskiing technique used. Subjective lower leg pain increased after the classic technique for the men from baseline to 1 minute postexercise and after the skate technique for the women. Significant 3-way interactions (technique × time × sex) were observed for the anterior (P = .002) and lateral (P = .009) compartment ICPs and lower leg pain (P = .005)., Conclusions: Postexercise anterior and lateral ICPs increased compared with preexercise ICPs after both classic and skate rollerskiing techniques. Lower leg pain is a primary symptom of CECS. The subjective lower leg pain 11-point Numeric Rating Scale results indicate that increases in lower leg ICPs sustained during Nordic rollerskiing may increase discomfort during activity. Our results therefore suggest that Nordic rollerskiing contributes to increases in ICPs, which may lead to the development of CECS.

The purpose of this study was to determine the level of knowledge that current and preservice high school (HS) physical educators and sport coaches possess regarding the principles and methods involved in youth resistance training (RT) and to determine if that knowledge was acceptable based on a predetermined criterion (passing score). A panel of 10 experts in RT or sport pedagogy used a Delphi technique to create a 90-question assessment (examination) that was administered to 287 HS physical educators and sport coaches and 140 university physical education teacher education (PETE) students. An analysis of the results revealed that neither group demonstrated the minimal knowledge necessary to design, implement, and supervise RT programs based on a passing score of 75%: HS physical educators/coaches, mean = 59.30, SD = 14.30, 95% confidence interval (CI) = 57.64-60.96], t(286) = -18.61, p = 0.000; university PETE students, mean = 56.61, SD = 16.59, 95% CI = 53.84-59.38, t(139) = -13.12, p = 0.000. The pass rate for physical educators and sport coaches was 14.3% and for university PETE students it was 20.7%. The results of this study indicate that both current and preservice physical educators and sport coaches need additional education and training specific to the design and implementation of RT programs for HS students. Given that school districts typically require their educators attend in-service training programs, it may be advisable to develop an in-service program that allows both current and preservice HS physical educators and sport coaches to earn an RT certification that specifically addresses the unique physical and psychosocial needs of school-aged youth.

In the floor exercise, a gymnast may receive a general composition score deduction associated with a lack of diverse tumbling sequences. Diversity in tumbling is defined as the ability to tumble both forward and backward, as well as twist and flip. A coach's ability to direct technical and physical training for these skill varieties is enhanced when thorough descriptions of the skills are available. The aim of this study was to describe and compare muscle activation of the lower extremity in various tumbling sequences characterized by differing body orientations. The stretch-shortening cycle actions during the take-off portion of four different tumbling sequences were analysed and the results compared across muscles and type of take-off (forward vs. backward, twisting vs. non-twisting). Thirteen female gymnasts performed three trials each of round-off flic-flac to backward layout and to backward layout with longitudinal axis twist, and front flic-flac to forward layout and to forward layout with longitudinal axis twist. Activation onset was assessed as an increase of the EMG of 200% above noise before initial floor contact. The EMG was normalized to peak values for each muscle bilaterally during each take-off. Results showed that muscle activation characteristics in the pre-activation and impact phase (contact to maximal floor depression) differed between tumbling series. Backward take-offs were characterized by longer contact times, greater relative activity of the gastrocnemius compared with the vastus lateralis during pre-activation, and greater biceps femoris activation during impact compared with forward take-offs. Twisting backward was associated with reduced muscle activity of the twisting limb, while twisting forward was associated with increased muscle activation on the twisting limb. These differential effects related to the specific nature of the take-off indicate that training to enhance the stretch-shortening cycle action in gymnasts must be specific to the orientation requirements of each specific skill.

Purpose: To compare areal bone mineral density (aBMD) of female winter sport athletes to healthy controls of similar age and body mass index (BMI)., Methods: Areal BMD (g x cm(-2)) of the whole body, lumbar spine (L2-L4), and right proximal femur were assessed by dual energy x-ray absorptiometry in athletes (N = 40; age: 26.1 +/- 5.7 yr; ht: 165.6 +/- 0.1 cm; wt: 63.0 +/- 6.5 kg; BMI: 23.0 +/- 1.9 kg x m(-2)) involved in speed skating (N = 9), snowboarding (N = 13), freestyle skiing (N = 3), biathlon (N = 8), bobsleigh, skeleton, luge (N = 7), and controls (N = 21; age: 26.0 +/- 5.1 yr; ht: 165.8 +/- 0.1 cm; wt: 62.8 +/- 5.9 kg; BMI: 22.9 +/- 1.3 kg x m(-2))., Results: Using independent t-tests, athletes had lower fat mass, percent body fat, and higher lean mass than controls (P < 0.001). Areal BMD was higher in athletes than controls for all skeletal sites (P

The VH domains of two human monoclonal antibodies, designated Mcg IgG1(lambda) and Yvo IgM(kappa), were particularly intractable to standard protein sequencing protocols. Peptides liberated from the VH domains of these proteins, using standard enzymatic or chemical cleavages, invariably precipitated during the procedures. Boiling in SDS containing buffers dissolved precipitates and the peptides were separated using SDS-PAGE. Fully overlapped VH sequences were obtained with a series of 'in-gel' cleavages, followed by passive/differential transfers of peptides onto PVDF membranes. Both the in-gel cleavages and passive transfers could be applied to 'wet' or 'dry' gels so that gels could be archived and used at a later date to obtain additional sequence information from a fragment of interest. Repetitive yields of even the most insoluble peptides were such that the sequences of various peptides from relatively complex mixtures of peptides could be assigned with confidence. Despite the overall success of the sequencing, we occasionally referred to electron density maps, calculated for crystals of the Fab of Yvo IgM, to resolve particular sequences and confirm ambiguous amino acid assignments. Methods we describe in this report should be generally useful for obtaining sequences of proteins with intractable cores and may find many applications in the 'post genomic era'., (Copyright 2002 John Wiley & Sons, Ltd.)

The X-ray structure of an immunoglobulin light-chain dimer isolated from the urine as a "Bence-Jones protein" from a patient with multiple myeloma and amyloidosis (Sea) was determined at 1.94 A resolution and refined to R and R(free) factors of 0.22 and 0.25, respectively. This "amyloidogenic" protein crystallized in the orthorhombic P2(1)2(1)2(1) space group with unit-cell parameters a = 48.28, b = 83.32, c = 112.59 A as determined at 100 K. In the vital organs (heart and kidneys), the equivalent of the urinary protein produced fibrillar amyloid deposits which were fatal to the patient. Compared with the amyloidogenic Mcg light-chain dimer, the Sea protein was highly soluble in aqueous solutions and only crystallized at concentrations approaching 100 mg ml(-1). Both the Sea and Mcg proteins packed into crystals in highly ordered arrangements typical of strongly diffracting crystals of immunoglobulin fragments. Overall similarities and significant differences in the three-dimensional structures and crystalline properties are discussed for the Sea and Mcg Bence-Jones proteins, which together provide a generalized model of abnormalities present in lambda chains, facilitating a better understanding of amyloidosis of light-chain origin (AL).

During a back tuck somersault, the angular velocity of the head is thought to surpass the visual system's ability to maintain a distinct and continuous picture of the environment. The primary objectives of this research were to determine if differences existed with regard to trunk and lower body kinematics, as well as landing balance, when gymnasts perform back tuck somersaults under different vision conditions. Ten female gymnasts (age = 11.6 +/- 2.67 years, competitive level = 8 +/- 1.15, and training time in gymnastics = 5.9 +/- 1.63 years) performed back tuck somersaults under 4 vision conditions while wearing electromagnetic sensors that allowed automatic digitizing. Although no significant differences were found between vision conditions with regard to timing, joint angles, and joint angular velocities, gymnasts were more stable at landing under conditions that allowed vision during either the entire somersault or the last half of the sumersault.

Although vision appears to enhance performance of somersaulting skills, few studies have investigated the source (foveal or ambient) of useful visual cues that can potentially be used by gymnasts during a somersault. Therefore, the primary objectives were to investigate the possible role of peripheral vision in the control of orientation and landing balance in a back tuck somersault. 10 female gymnasts (age = 11.6 +/- 2.7 yr., competitive level = 8 +/- 1.2, training time in gymnastics = 5.9 +/- 1.6 yr.) performed back tuck somersaults under four visual conditions (full visual field, horizontal peripheral vision limited to 100 degrees, horizonal peripheral vision limited to 60 degrees, and no vision) while wearing electromagnetic sensors that allowed automatic digitizing. Analysis yielded no statistically significant difference on any of the kinematic variables among vision conditions. Despite limiting the gymnasts' available horizontal peripheral vision, joint angles, angular velocities, and timing remained very similar. There were no statistically significant differences in landing balance between the conditions of full vision, 100 degrees peripheral vision, and 60 peripheral vision. However, gymnasts were less stable at landing when vision was absent as compared to the three other vision conditions.

Background: Cardiorespiratory fitness is favorably associated with most modifiable coronary heart disease (CHD) risk factors. Findings are limited, however, by few data for women, persons with existing CHD, and low-risk populations. In the present study, we described cross-sectional associations between cardiorespiratory fitness and CHD risk factors in a large cohort of middle-aged men and women, of whom the majority were LDS Church members (Mormons), with and without existing CHD., Methods and Results: Comprehensive health examinations were performed on 3232 men (age 45.9+/-10.8 years) and 1128 women (age 43.8+/-12.8 years) between 1975 and 1997. Maximal treadmill exercise testing was used to categorize those with (12% of the men and 10% of the women) and those without CHD into age- and sex-specific cardiorespiratory fitness quintiles. After adjustments for age, body fat, smoking status, and family history of CHD, favorable associations were observed between fitness and most CHD risk factors among men and women, regardless of CHD status., Conclusions: These data indicate that enhanced levels of cardiorespiratory fitness may confer resistance to elevations in CHD risk factors even in a low-risk sample of middle-aged men and women. Furthermore, these findings reinforce current public health recommendations that advocate increased national levels of physical activity and cardiorespiratory fitness for primary and secondary CHD prevention.

The jogging minitrampoline is a common tool for exercise and rehabilitation that is lauded as helpful in reducing lower extremity stresses. The deformable bed of the minitrampoline may result in altered jogging mechanics of the subtalar joint, potentially leading to uncharacteristic mechanics of the lower extremity. The purpose of this study was to examine eversion of the subtalar joint in subjects jogging on the minitrampoline vs. a wooden floor surface. Subjects were instrumented with a flexible electrogoniometer (elgon) taped from the heel to the gastrocnemius along the Achilles tendon. The elgon was interfaced to a personal computer. Data were examined for the average maximal eversion values of five steps during jogging in two experiments. Results of the first experiment (N = 27) indicated significantly greater mean maximal eversion angles while jogging on the minitrampoline than on the floor. The second experiment involved 10 male and 10 female subjects jogging for 20 minutes with a counterbalanced sequence of jogging conditions, alternating between the floor and the minitrampoline. The second experiment indicated that maximal eversion angles were significantly greater on the minitrampoline than on the floor and increasing jogging time resulted in greater eversion angles and a significant interaction between jogging condition and time. Results suggest that people who should avoid valgus deviations to the lower leg should not jog on the jogging minitrampoline.

The purpose of the study was to compare anaerobic power and anaerobic capacity test scores between young active men and women. Three performance measures of anaerobic power and two of anaerobic capacity were administered to a sample comprising 52 male and 50 female college students (means age = 21.4 yrs). Results indicated significant differences between men and women in body height, weight and per cent fat, in fat free mass (FFM), anaerobic power, and anaerobic capacity when recorded as gross work completed and relative to body weight. However, these differences are reduced when data is adjusted for body weight and further reduced when corrected for FFM. The study found no significant differences between men and women in either anaerobic power or anaerobic capacity when values were given relative to FFM.

This study was undertaken in order to develop norms for the Wingate test for physically active young men and women, and also to compare mean power measures obtained from the Wingate test with those obtained from another similar cycle ergometer test. A total of 112 males and 74 females aged 18 to 28 years comprised the subject pool. Data collected from the Wingate test included mean power for 30 s, peak power for 5 s, and a percent fatigue index. Data from the second test (Katch test) included mean power for both 30 s and 40 s. Percentile norms and descriptive statistics were generated as were multiple regression equations for prediction of mean power between the two different tests. Correlations between the two tests ranged from .66 to .87. Comparisons among data derived from this study and those reported for other athletic groups are also given.

*Study conducted as part of thesis submitted by R.D.C. in partial fulfillment of the requirements for the degree of Master of Science. The purpose of this investigation was to evaluate isokinetic characteristics of the knee in female, ballet and modern, professional and university dancers in order to evaluate possible differences among the groups. A total of 37 dancers with a mean age of 24.9 years was tested using a Cybex II dynamometer. A multiple analysis of variance (MANOVA) indicated that the ballet dancers had significantly higher H/Q ratios than modern dancers at three speeds (p < 0.024). Post hoc procedures indicated that the professional ballet dancers (PB) had significantly higher H/Q ratios than all other groups at 180 degrees /sec (p < 0.05). Also, although most of these dancers demonstrated normal peak torque/body weight values for knee extension and flexion, specific weaknesses were observed in the force decay rate of the quadriceps curves. It was concluded that these theatrical dancers were not a homogeneous group in terms of certain isokinetic characteristics.J Orthop Sports Phys Ther 1988;9(12):410-418.

In an attempt to determine whether certain physical characteristics discriminated between people with and without herniated intervertebral lumbar discs, volunteers (N = 40) who were diagnosed as having a herniated lumbar disc were compared to control subjects (N = 40) who had been randomly selected and matched by age and sex. All subjects completed a questionnaire to determine the history of their back injury and a description of their exercise behavior patterns. Body composition was estimated by hydrostatic weighing. Maximum oxygen consumption was predicted using the Astrand-Ryhming nomogram. Strength scores were determined from a battery of cable tensiometer tests. Dependent variables were analyzed using a multiple analysis of variance (MANOVA). Using discriminant analysis, as a post hoc test, predicted maximum oxygen consumption was shown to account for the difference between the groups (P less than .002). The control subjects' values were higher than the patients' values. Subjects' exercise history indicated no differences between the groups relative to the time period preceding the onset of injury (P greater than .05). The exercise activity of patients was significantly reduced after injury (P less than .001). An average of 87 days elapsed between the onset of injury to the date of fitness testing.