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Jennifer White, Joanna Scurr and Wendy Hedger

Comparisons of breast support requirements during overground and treadmill running have yet to be explored. The purpose of this study was to investigate 3D breast displacement and breast comfort during overground and treadmill running. Six female D cup participants had retro-reflective markers placed on the nipples, anterior superior iliac spines and clavicles. Five ProReflex infrared cameras (100 Hz) measured 3D marker displacement in four breast support conditions. For overground running, participants completed 5 running trials (3.1 m/s ± 0.1 m/s) over a 10 m indoor runway; for treadmill running, speed was steadily increased to 3.1 m/s and 5 gait cycles were analyzed. Subjective feedback on breast discomfort was collected using a visual analog scale. Running modality had no significant effect on breast displacement (p > .05). Moderate correlations (r = .45 to .68, p < .05) were found between breast discomfort and displacement. Stride length (m) and frequency (Hz) did not differ (p < .05) between breast support conditions or running modalities. Findings suggest that breast motion studies that examine treadmill running are applicable to overground running.

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Joanna Scurr, Jennifer White and Wendy Hedger

This study aimed to assess the trajectory of breast displacement in 3 dimensions during walking and running gait, as this may improve bra design and has yet to be reported. Fifteen D-cup participants had reflective markers attached to their nipples and trunk to monitor absolute and relative breast displacement during treadmill walking (5 kph) and running (10 kph). During the gait cycle, the breast followed a figure-of-eight pattern with four movement phases. Despite a time lag in resultant breast displacement compared with the trunk, similar values of breast displacement were identified across each of the four phases. Fifty-six percent of overall breast movement was vertical, suggesting that 3-D assessment and the elimination of trunk movement in 6 degrees of freedom are essential to accurately report breast displacement during the gait cycle.

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Claire Bridgman, Joanna Scurr, Jennifer White, Wendy Hedger and Heather Galbraith

Anecdotal reports suggest two-step star jumps cause excessive breast movement and discomfort, leading to recommendations for this activity as a diagnostic tool to determine effective breast support in a retail environment. The aim was to investigate multiplanar bare-breast kinematics during the two-step star jump and to establish the relationship between breast kinematics, discomfort and cup size. Thirty-nine females completed five two-step star jumps with no breast support after which breast discomfort was rated. To establish relative breast kinematics infrared cameras tracked the 3D co-ordinates of breast and body markers. Maximum resultant breast displacement, velocity and acceleration during jumping reached 18.7 cm, 93.1 cm·s−1 and 3.6 g, respectively. Significantly more vertical breast displacement (p < 0.01) and velocity (p < 0.01) occurred compared with mediolateral and anteroposterior kinematics. Breast discomfort increased as cup size increased (r = .61). Two-step star jumping stimulated multiplanar breast kinematics and high levels of breast discomfort. Therefore, this activity may be useful in a retail outlet to determine the function and comfort of a sports bra.

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Erin White, Jennifer D. Slane, Kelly L. Klump, S. Alexandra Burt and Jim Pivarnik

Background:

Knowing the extent to which genetic and environmental factors influence percent body fatness (%Fat) and physical activity (PA) would be beneficial, since both are tightly correlated with future health outcomes. Thus, the purpose was to evaluate sex differences in genetic and environmental influences on %Fat and physical activity behavior in male and female adolescent twins.

Methods:

Subjects were adolescent (age range 8.3 to 16.6 yr) twins. %Fat (n = 518 twins) was assessed by bioelectrical impedance analysis (BIA) and PA (n = 296 twins) was measured using 3-Day PA Recall. Each activity was converted to total MET-minutes. Univariate twin models were used to examine sex differences in genetic and environmental factors influencing %Fat and PA.

Results:

%Fat was influenced by genetic effects in both boys and girls (88% and 90%, respectively), with slightly higher heritability estimates for girls. PA was influenced solely by environmental effects for both sexes with higher shared environmental influences in boys (66%) and higher nonshared effects in girls (67%).

Conclusions:

When developing interventions to increase PA in adolescents, it is important to consider the environment in which it takes place as it is the primary contributor to PA levels.

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Jennifer L. Gay, Sara W. Robb, Kelsey M. Benson and Alice White

Background:

The Social Vulnerability Index (SVI), a publicly available dataset, is used in emergency preparedness to identify communities in greatest need of resources. The SVI includes multiple socioeconomic, demographic, and geographic indicators that also are associated with physical fitness and physical activity. This study examined the utility of using the SVI to explain variation in youth fitness, including aerobic capacity and body mass index.

Methods:

FITNESSGRAM data from 2,126 Georgia schools were matched at the census tract level with SVI themes of socioeconomic, household composition, minority status and language, and housing and transportation. Multivariate multiple regression models were used to test whether SVI factors explained fitness outcomes, controlling for grade level (ie, elementary, middle, high school) and stratified by gender.

Results:

SVI themes explained the most variation in aerobic fitness and body mass index for both boys and girls (R 2 values 11.5% to 26.6%). Socioeconomic, Minority Status and Language, and Housing and Transportation themes were salient predictors of fitness outcomes.

Conclusions:

Youth fitness in Georgia was related to socioeconomic, demographic, and geographic themes. The SVI may be a useful needs assessment tool for health officials and researchers examining multilevel influences on health behaviors or identifying communities for prevention efforts.

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Cori Sinnott, Hayley M. White, Jennifer W. Cuchna and Bonnie L. Van Lunen

Clinical Scenario:

Achilles tendinopathy is a painful condition commonly affecting the general and athletic population. It presents with localized pain, stiffness, and swelling in the midportion of the Achilles tendon. The physical stress placed on the tendon results in microtrauma, which leads to subsequent inflammation and degeneration. While it is not surprising that this condition affects the physically active, nearly one-third of Achilles tendinopathy cases occur in sedentary individuals. Etiology for this condition stems from a change in loading patterns and/or overuse of the tendon, resulting in microscopic tearing and degenerative changes. There are numerous causes contributing to the maladaptive response in these patients, such as mechanical, age-related, genetic, and vascular factors. The treatment for these patients is typically load management and eccentric strengthening of the gastrocnemius–soleus complex. Unfortunately, conservative treatment can lead to surgical intervention in up to 45% of cases. A relatively new phenomenon in the treatment of this condition is the use of autologous blood injections (ABI) and platelet-rich plasma injections (PRPI). This need for a less invasive treatment fostered more investigation into ABI and PRPI to treat these nonresponsive patients. However, the evidence concerning the effectiveness of these treatments in patients with Achilles tendinopathy has not been synthesized.

Focused Clinical Question:

In patients with Achilles tendinopathy, how do variations of ABI and PRPI compared with a placebo and/or eccentric training affect pain and function?

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Sarah Warner, Jennifer White, Shawn Hueglin, Elena Estana-Johnson, Chris Schoen and Lynda Ransdell

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Justin J. Merrigan, James J. Tufano, Jonathan M. Oliver, Jason B. White, Jennifer B. Fields and Margaret T. Jones

Purpose: To examine rest redistribution (RR) effects on back squat kinetics and kinematics in resistance-trained women. Methods: Twelve women from strength and college sports (5.0 [2.2] y training history) participated in the randomized crossover design study with 72 hours between sessions (3 total). Participants completed 4 sets of 10 repetitions using traditional sets (120-s interset rest) and RR (30-s intraset rest in the middle of each set; 90-s interset rest) with 70% of their 1-repetition maximum. Kinetics and kinematics were sampled via force plate and 4 linear position transducers. The greatest value of repetitions 1 to 3 (peak repetition) was used to calculate percentage loss, [(repetition 10–peak repetition)/(peak repetition) × 100], and maintenance, {100–[(set mean–peak repetition)/(peak repetition)] × 100}, of velocity and power for each set. Repeated-measures analysis of variance was used for analyses (P < .05). Results: Mean and peak force did not differ between conditions. A condition × repetition interaction existed for peak power (P = .049) but not for peak velocity (P = .110). Peak power was greater in repetitions 7 to 9 (P < .05; d = 1.12–1.27) during RR. The percentage loss of velocity (95% confidence interval, –0.22% to –7.22%; P = .039) and power (95% confidence interval, –1.53% to –7.87%; P = .008) were reduced in RR. Mean velocity maintenance of sets 3 (P = .036; d = 1.90) and 4 (P = .015; d = 2.30) and mean power maintenance of set 4 (P = .006; d = 2.65) were greater in RR. Conclusion: By redistributing a portion of long interset rest into the middle of a set, velocity and power were better maintained. Therefore, redistributing rest may be beneficial for reducing fatigue in resistance-trained women.

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Katherine B. Gunter, Jennifer De Costa, Karen N. White, Karen Hooker, Wilson C. Hayes and Christine M. Snow

This study assessed changes in balance self-efficacy (BSE) over 1 year in community-dwelling elderly, compared changes in BSE between fallers and nonfallers, and assessed the relationship between specific balance and mobility risk factors for side falls and BSE scores. Elderly fallers (n = 67; 80.2 ± 5.9 years) and nonfallers (n = 75; 79.4 ± 4.9), categorized based on self-reported falls over 1 year, were tested at baseline on postural sway, hip-abduction strength, lateral-stepping velocity, tandem walk, and get-up-and-go and given a BSE questionnaire. Fallers had lower BSE scores than nonfallers did (141.6 ± 33.5 and 154.9 ± 25.4; p = .008). BSE did not change over 1 year. In stepwise regression, BSE scores were predictive of time on the get-up-and-go, mediolateral sway, and tandem walk independent of age, height, and strength (p < .001). The BSE scale might be useful for screening individuals at risk for injurious falls because it is inexpensive and noninvasive.

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Lynda B. Ransdell, Sarah Toevs, Jennifer White, Shelley Lucas, Jean L. Perry, Onie Grosshans, Diane Boothe and Sona Andrews

In higher education in the United States, women are often underrepresented in leadership positions. When women try administration, they face a higher rate of attrition than their male counterparts. Given the lack of women in leadership positions and the failure of the academy to retain women administrators, a group of women administrators and faculty with many collective years of experience in higher education assembled to write this paper. Our writing group consisted of 2 Chairs, 2 Deans, 1 Associate Dean, 2 pre-tenure faculty members, and a Provost, representing four different institutions. The authors of this paper suggest that applying the proposed model of transformational leadership within the field of Kinesiology may have a two-fold benefit. It may increase the number of women in administrative positions and it may extend how long women choose to serve in an administrative capacity. Components of the model include developing personal and professional characteristics that motivate faculty to perform beyond expectations, and understanding gender-related and kinesiology-specific challenges of administration. In addition, recommendations are made for pursuing careers in administration, and for pursuing future research projects. We hope that through this paper, we have started an important and open discussion about women in leadership roles, and ultimately, encouraged some prospective leaders to consider a career in higher education administration.