PubMed Health⌕ Search

Biomedical subjects

B B Shultz

Publications and source records attributed to B B Shultz.

10 recordsLinked to original sources
PubMed2001

The role of vision in control of orientation in a back tuck somersault.

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.

Acceleration↗
PubMed2001

Peripheral vision and back tuck somersaults.

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.

Adolescent↗
PubMed2000

Cardiorespiratory fitness and coronary heart disease risk factors: the LDS Hospital Fitness Institute cohort.

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.

Cohort Studies↗
PubMed1995

A comparison of subtalar joint maximal eversion while jogging on the minitrampoline and floor.

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.

Adult↗
PubMed1994

The effects of aerobic exercise after lumbar microdiscectomy.

STUDY DESIGN: This study determined whether lumbar discectomy patients could endure an aerobic exercise program sufficient to achieve a training effect, and whether any functional advantages were derived. METHODS: Trained volunteers (n = 19) were compared with untrained control subjects (n = 18) after a 12-week aerobic and rehabilitation exercise program. Subjects completed a maximal graded exercise test, a hydrostatic weighing test, and a battery of self-report inventories. RESULTS: Using a discriminant analysis, as a post hoc test, maximal oxygen consumption was found to be the factor responsible for the difference between the groups (P < 0.006). CONCLUSION: Oxygen consumption was more than three times as important as any other single variable in differentiating between the groups.

Adult↗
PubMed1989

Norms for the Wingate anaerobic test with comparison to another similar test.

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.

Adolescent↗
PubMed1987

Physical characteristics of patients with herniated intervertebral lumbar discs.

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.

Adipose Tissue↗
PubMed1986

Gender comparisons in anaerobic power and anaerobic capacity tests.

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.

Adipose Tissue↗
PubMedDate not supplied

Women's gymnastics injuries. A 5-year study.

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.

Adult↗