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  • Author: A.M. Johnson x
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Louis M. Ferreira, Graham J.W. King and James A. Johnson

The anterior bundle of the medial collateral ligament (AMCL) of the elbow is commonly injured in patients with elbow dislocations and in throwing athletes. This in-vitro study quantified tension in the native AMCL throughout elbow flexion for different arm positions. We conducted passive and simulated active elbow flexion in seven fresh-frozen cadaveric upper extremities using an established motion simulator. Motions were performed in the valgus and vertical positions from 20–120° while measuring AMCL tension using a custom transducer. Average AMCL tension was higher in the valgus compared to vertical position for both active (p = 0.03) and passive (p = 0.01) motion. Peak AMCL tension was higher in the valgus position for active (p = 0.02) and passive (p = 0.01) motion. There was no significant difference in AMCL tension between active and passive motion in the valgus (p = 0.15) or vertical (p = 0.39) positions. In the valgus position, tension increased with elbow flexion from 20–70° for both active (p = 0.04) and passive (p = 0.02) motion, but not from 70–120°. This in-vitro study demonstrated that AMCL tension increases with elbow flexion, and is greater in the valgus position relative to the vertical position. This information has important implications to the desired target strength of repair and reconstruction techniques.

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Danielle M. Thiel, Fatima Al Sayah, Jeff Vallance, Steven T. Johnson and Jeffrey A. Johnson

Background:

The objective was to investigate the longitudinal relationship between physical activity and health-related quality of life (HRQL) in adults with type 2 diabetes.

Methods:

Data were from a prospective cohort of adults with type 2 diabetes. Weekly moderate-to-vigorous physical activity (MVPA) was reported using the Godin Leisure-Time Physical Activity Questionnaire, and HRQL was reported using the SF-12 and 5-level EQ-5D. Participants were categorized based on current weekly MVPA recommendations. Multivariable linear regression was used to explore associations between MVPA and HRQL, and multinomial logistic regression was used to assess the direction of change in HRQL after 1 year.

Results:

Mean age of participants (N = 1948) was 64.5 ± 10.8 years and 45% were female. Participants reported a mean of 84.1 ± 172.4 min of MVPA/week, and 21% (n = 416) met weekly MVPA recommendations. MVPA was associated with differences in the physical functioning (b = 5.42; P < .001), general health (b = 2.45; P = .037), and vitality (b = 2.83; P = .016) SF-12 dimensions. Participants who met recommendations were less likely to report a decline (vs. no change) in EQ-5D index score (OR = 0.75; 95% CI [0.57, 0.99]), and SF-12 physical component summary (OR = 0.67; 95% CI [0.50, 0.90]), compared with participants not meeting recommendations.

Conclusions:

Participants who met weekly MVPA recommendations reported better physical functioning and were more likely to maintain their physical and overall HRQL over time.

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J. Jimenez-Pardo, J.D. Holmes, M.E. Jenkins and A.M. Johnson

Physical activity is generally thought to be beneficial to individuals with Parkinson’s disease (PD). There is, however, limited information regarding current rates of physical activity among individuals with PD, possibly due to a lack of well-validated measurement tools. In the current study we sampled 63 individuals (31 women) living with PD between the ages of 52 and 87 (M = 70.97 years, SD = 7.53), and evaluated the amount of physical activity in which they engaged over a 7-day period using a modified form of the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD). The PASIPD was demonstrated to be a reliable measure within this population, with three theoretically defensible factors: (1) housework and home-based outdoor activities; (2) recreational and fitness activities; and (3) occupational activities. These results suggest that the PASIPD may be useful for monitoring physical activity involvement among individuals with PD, particularly within large-scale questionnaire-based studies.

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C. Shanthi Jacob Johnson, Anita M. Myers, Lynn M. Scholey, Elizabeth V. Cyarto and Nancy A. Ecclestone

The Home Support Exercise Program (HSEP) targets frail older adults. After a 4-hr training workshop, home-support workers (HSWs) encourage clients to do a simple, progressive set of 10 exercises during regular visits. Exercise compliance and functional performance were examined in 60 clients who received the HSEP, compared with 38 clients whose HSWs had not received HSEP training. Both groups were primarily female, average age 82, and many of them used walking aids. The 40 HSEP clients who continued with the program over 4 months showed good compliance and significant improvement on several indicators: timed up-and-go, sit-to-stand, 6-min walk, balance confidence, and well-being. Conversely, the comparison group declined on several measures. The findings support the effectiveness of the HSEP, as well as the importance of regular and ongoing support from HSWs for this population.

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Sam T. Johnson, Grace M. Golden, John A. Mercer, Brent C. Mangus and Mark A. Hoffman

Context:

Form skipping has been used to help injured athletes progress to running. Because little research has been done on form-skipping mechanics, its justification as a progression to running exercises is unclear.

Objective:

To compare ground-reaction forces (GRF) during form skipping and running in healthy subjects at clinically relevant speeds, 1.75 m/s and 3.83 m/s, respectively.

Design:

Dependent t tests (α = .05).

Setting:

Sports-injury research center.

Participants:

9 male college athletes (age 20 ± 1.33 years, mass 848.4 ± 43.24 N, height 1.80 ± 0.07 m).

Main Outcome Measures:

Average (Fz avg) and maximum (Fz max) vertical GRF and (Fy) braking impulse were compared.

Results:

Fz avg and Fz max were greater during running than during form skipping (P < .05). Braking impulses were not different (P > .05).

Conclusions:

It appears that Fz, but not the Fy, GRF might explain why form skipping might be an appropriate progression to running.

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Phillip Ward, Tim M. Barrett, Sharon A. Evans, Panayiotis Doutis, Phong T. Nguyen and Melissa K. Johnson

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Andrew M. Johnson, Philip A. Vernon, Quincy J. Almeida, Linda L. Grantier and Mandar S. Jog

The effect of a precue on improving movement initiation (i.e., reaction time; RT) is well understood, whereas its influence on movement execution (i.e., movement time; MT) has rarely been examined. The current study investigated the influence of a directional precue (i.e., left vs. right) on the RT and MT of simple and discrete bi-directional movements in a large sample of Parkinson's disease patients and healthy control participants. Both patients and controls were tested twice, with testing sessions separated by 2 hours. Patients were tested first following an overnight levodopa withdrawal and again after they had taken their medication. Both patients and controls demonstrated a significant RT improvement when information was provided in advance. MT in both healthy participants and medicated patients was, however, slower with the provision of advance information, while unmedicated patients showed no significant MT effects. These results suggest that while the basal ganglia may not be involved in motor program selection, they may dynamically modulate movement execution.

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John A. DiBella II, Emily M. Johnson and Marco E. Cabrera1

We compared maximal exercise parameters obtained using both a ramped Bruce (BR) and a standard Bruce treadmill protocol (BS) in 44 healthy children (9.9 – 1.9 yr) and adolescents (15.9 – 1.7 yr). The average weight and height for children was 36.7 – 10.7 kg and 141.2 – 13.2 cm, while for adolescents was 64.4 – 13.9 kg and 168.9 – 7.5 cm. No significant differences were found in peak heart rate (HRpeak) between protocols for children (BS: 198 – 10; BR: 196 – 11 bpm) or adolescents (BS:193 – 2; BR:192 – 11 bpm). Peak oxygen uptake (V̇O2peak) was also not significantly different for children (BS: 1.81 – 0.64; BR: 1.84 – 0.74 L/min) or adolescents (BS: 2.66 – 0.61; BR: 2.72 – 0.67 L/min). Based on our results, we conclude that equivalent peak HR and V̇O2 values can be obtained in normal children and adolescents using a standard or a ramped Bruce protocol.

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Sharon A. Evans, Joan M. Eckerson, Terry J. Housh and Glen O. Johnson

This investigation examined age related differences in the muscular power of the arms in high school wrestlers. Seventy-five volunteers (M age ±SD = 16.3 ±1.2 yrs) were stratified into four age groups (≤15.00; 15.01−16.00; 16.01−17.00, and ≥17.01 yrs) corresponding approximately to the freshman through senior years of high school. Mean power (MP) and peak power (PP) were measured using an arm crank Wingate Anaerobic Test, and body composition was assessed via underwater weighing. The results indicated significant (p<0.05) group differences for absolute MP and PP as well as for relative MP and PP (covaried for body weight). No significant differences were found when MP and PP were adjusted for fat-free weight (FFW). The results suggested that the age related increases in muscular power of the arms were a function of increases in FFW across age.

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Elizabeth A. Wanless, Ryan M. Brewer, James E. Johnson and Lawrence W. Judge

To prepare students for employment in sport, many sport management programs involve students in revenue generation activities, such as ticket or sponsorship sales. Literature evaluating student perceptions of this specific type of experiential learning remains sparse. This constructivist qualitative study evaluated student perceptions of learning from two courses containing experiential revenue generation projects. Data were gathered via structured-question electronic survey. Fifty-one of 60 students participated. Results generally supported previous research conclusions; conducting experiential learning projects increases skill and professional development and offers a realistic career preview but demands significant time commitment. Important contradictions, however, were present in comparison with past literature. The unique nature of sales-based projects involving students in ticket sales and sponsorship sales served as a platform for students to develop critically important interpersonal skills. This benefit was not identified in studies evaluating experiential learning opportunities that did not contain a sales-based component.