Browse

You are looking at 41 - 50 of 4,751 items for :

  • Sport and Exercise Science/Kinesiology x
  • Athletic Training, Therapy, and Rehabilitation x
  • Refine by Access: All Content x
Clear All
Restricted access

Andrea Stracciolini, Caitlin M. McCracken, William P. Meehan III, and Matthew D. Milewski

Purpose: To study mental health, sleep duration, and daytime sleepiness in young athletes. Methods: A cross-sectional questionnaire study was conducted. The main outcome measures included sleep duration and daytime sleepiness. Results: Study participants included 756 athletes with a mean age of 13.5 years. A total of 39% (n = 296/756) reported not meeting current sleep recommendations for age. Athletes >12 years and with a self-reported anxiety and/or depression history were less likely to meet sleep recommendations and showed higher daytime sleepiness (adjusted odds ratio [aOR] = 1.29, 95% confidence interval [CI] [1.2, 1.4], β [SE] = 3.06 [0.74], respectively). Athletes with goal-oriented reasons for playing versus enjoyment (52% vs. 35%, aOR = 1.70, 95% CI [1.12, 2.58]) were less likely to meet sleep recommendations. Night time internet access and weeknight homework hours were negatively associated with sleep recommendations (aOR = 1.68, 95% CI [1.68, 2.47] and aOR = 3.11, 95% CI [1.82, 5.3]) and positively associated with daytime sleepiness (β [SE] = 1.44 [0.45] and 2.28 [0.59]). Conclusions: Many young athletes are not meeting sleep recommendations. Associated factors include mental health, reasons for play, internet access, and homework demand.

Restricted access

Young-Hoo Kwon, Noelle J. Tuttle, Cheng-Ju Hung, Nicholas A. Levine, and Seungho Baek

The purpose of this study was to investigate the linear relationships among the hand/clubhead motion characteristics in golf driving in skilled male golfers (n = 66; handicap ≤ 3). The hand motion plane (HMP) and functional swing plane (FSP) angles, the HMP–FSP angle gaps, the planarity characteristics of the off-plane motion of the clubhead, and the attack angles were computed from the drives captured by an optical motion capture system. The HMP angles were identified as the key variables, as the HMP and FSP angles were intercorrelated, but the plane angle gaps, the planarity bias, and the attack angles showed correlations to the HMP angles primarily. Three main swing pattern clusters were identified. The parallel HMP–FSP alignment pattern with a small direction gap was associated with neutral planarity and planar swing pattern. The inward alignment pattern with a large inward direction gap was characterized by flat planes, follow-through-centric planarity, spiral swing pattern, and inward/downward impact. The outward alignment pattern with a large outward direction gap was associated with steep planes, downswing-centric planarity, reverse spiral swing, and outward/upward impact. The findings suggest that practical drills targeting the hand motion pattern can be effective in holistically reprogramming the swing pattern.

Restricted access

Witaya Mathiyakom, Rand Wilcox, and Jill L. McNitt-Gray

Studying how elite athletes satisfy multiple mechanical objectives when initiating well-practiced, goal-directed tasks provides insights into the control and dynamics of whole-body movements. This study investigated the coordination of multiple body segments and the reaction force (RF) generated during foot contact when regulating forward angular impulse in backward translating tasks. Six highly skilled divers performed inward somersaults (upward and backward jump with forward rotation) and inward timers (upward and backward jump without rotation) from a stationary platform. Sagittal plane kinematics and RFs were recorded simultaneously during the takeoff phase. Regulation of the forward angular impulse was achieved by redirecting the RF about the total body center of mass. Significantly more backward-directed RF was observed during the first and second peak horizontal RF of the inward somersaults than the inward timers. Modulation of the horizontal RF altered the RF direction about the center of mass and the lower-extremity segments. Backward leg and forward trunk orientation and a set of relatively large knee extensor and small hip flexor net joint moments were required for forward angular impulse generation. Understanding how the forward angular impulse is regulated in trained individuals provides insights for clinicians to consider when exploring interventions related to fall prevention.

Open access

John H. Challis and Stephen J. Piazza

Restricted access

Stephen P. Hebard, James E. Bissett, Emily Kroshus, Emily R. Beamon, and Aviry Reich

Sport coaches can play an influential role in athletes’ mental health help seeking through purposeful communication, destigmatization of mental health concerns, and supportive relationships. To positively engage in these behaviors, coaches require mental health knowledge (or literacy), positive attitudes about that knowledge, and self-efficacy to use that knowledge. Guided by a multidimensional health literacy framework, we conducted a content analysis of web content and scholarly literature to identify health education programming for coaches that addressed athlete mental health. A purposive sample of Olympic National Governing Bodies, collegiate athletic associations, high school sport associations, youth sport governing bodies, and the scholarly literature were analyzed. We found inconsistent programming regarding a range of mental health disorders, behaviors critical to mental health promotion, and critical components of mental health literacy. Implications and next steps for mental health literacy support for coaches are discussed.

Restricted access

Paige E. Rice, Kiisa Nishikawa, Kevin A. Zwetsloot, Amelia S. Bruce, Caroline D. Guthrie, and Sophia Nimphius

The purpose of this investigation was to elucidate whether ankle joint stretch-shortening cycle performance, isometric and isokinetic plantarflexion strength, and maximal Achilles tendon force and elongation differ between dancers, endurance runners, and untrained controls. To differentiate between dancers, endurance runners, and controls, the authors measured maximal Achilles tendon force and elongation during isometric ramp contractions with ultrasonic imaging, maximal isometric and isokinetic plantarflexion strength with dynamometry, and stretch-shortening cycle function during countermovement hopping and 30-cm drop hopping with a custom-designed sled. The Achilles tendon of dancers elongated significantly (P ≤ .05) more than runners and controls. Dancers were significantly stronger than controls during isometric contractions at different ankle angles. Concentric and eccentric strength during isokinetic contractions at 60°·s−1 and 120°·s−1 was significantly higher in dancers and runners than controls. Dancers hopped significantly higher than runners and controls during hopping tasks. Dancers also possessed significantly greater countermovement hop relative peak power, drop hop relative impulse, and drop hop relative peak power than controls. Finally, dancers reached significantly greater velocities during countermovement hops than runners and controls. Our findings suggest dancing and running require or likely enhance plantarflexion strength. Furthermore, dancing appears to require and enhance ankle joint stretch-shortening cycle performance and tendon elongation.

Restricted access

Declan A. Patton, Colin M. Huber, Susan S. Margulies, Christina L. Master, and Kristy B. Arbogast

Field studies have evaluated the accuracy of sensors to measure head impact exposure using video analysis, but few have studied false negatives. Therefore, the aim of the current study was to investigate the proportion of potential false negatives in high school soccer head impact data. High school athletes (23 females and 31 males) wore headband-mounted Smart Impact Monitor-G impact sensors during competitive soccer games. Video footage from 41 varsity games was analyzed by 2 independent reviewers to identify head contact events, which were defined as visually observed contact to the head. Of the 1991 video-identified head contact events for which sensors were functioning and worn by the players, 1094 (55%) were recorded by the sensors. For female players, 45% of video-identified head contact events were recorded by the sensor compared with 59% for male players. For both females and males, sensitivity varied by impact mechanism. By quantifying the proportion of potential false negatives, the sensitivity of a sensor can be characterized, which can inform the interpretation of previous studies and the design of future studies using head impact sensors. Owing to the difficulty in obtaining ground truth labels of head impacts, video review should be considered a complementary tool to head impact sensors.

Restricted access

Benoit R. Lafleur, Alyssa M. Tondat, Steven P. Pretty, Marina Mourtzakis, and Andrew C. Laing

Trochanteric soft tissue thickness (TSTT) is a protective factor against fall-related hip fractures. This study’s objectives were to determine: (1) the influence of body posture on TSTT and (2) the downstream effects of TSTT on biomechanical model predictions of fall-related impact force (F femur) and hip fracture factor of risk. Ultrasound was used to measure TSTT in 45 community-dwelling older adults in standing, supine, and side-lying positions with hip rotation angles of −25°, 0°, and 25°. Supine TSTT (mean [SD] = 5.57 [2.8] cm) was 29% and 69% greater than in standing and side-lying positions, respectively. The F femur based on supine TSTT (3380 [2017] N) was 19% lower than the standing position (4173 [1764] N) and 31% lower than the side-lying position (4908 [1524] N). As factor of risk was directly influenced by F femur, the relative effects on fracture risk were similar. While less pronounced (<10%), the effects of hip rotation angle were consistent across TSTT, F femur, and factor of risk. Based on the sensitivity of impact models to TSTT, these results highlight the need for a standardized TSTT measurement approach. In addition, the consistent influence of hip rotation on TSTT (and downstream model predictions) support its importance as a factor that may influence fall-related hip fracture risk.

Restricted access

Linh Q. Vu, Rahul Agrawal, Mahdi Hassan, and Nils A. Hakansson

Human rolling, as turning in bed, is a fundamental activity of daily living. A quantitative analysis of rolling could help identify the neuromusculoskeletal disorders that prohibit rolling and develop interventions for individuals who cannot roll. This study sought to determine whether crossing the arms over the chest would alter fundamental coordination patterns when rolling. Kinematic data were collected from 24 subjects as they rolled with and without their arms crossed over their chest. Crossing the arms decreased the mean peak angular velocities of the shoulders (p = .001) and pelvis (p = .013) and influenced the mean duration of the roll (p = .057). There were no fundamental differences in shoulder and pelvis coordination when rolling with the arms crossed over the chest, implying that the arms may not have a major role in rolling.