meet PA guidelines. 5 This suggests an urgent need for intervention to improve children’s PA. The availability of play equipment at home is modifiable and could be targeted in interventions. The home is the most proximal and influential environment for children and is a prime context for intervention
Katrina M. Moss, Annette J. Dobson, Kimberley L. Edwards, Kylie D. Hesketh, Yung-Ting Chang and Gita D. Mishra
Jonathan S. Akins, Nicholas R. Heebner, Mita Lovalekar and Timothy C. Sell
Ankle ligament sprains are the most common injury in soccer. The high rate of these injuries demonstrates a need for novel data collection methodologies. Therefore, soccer shoes and shin guards were instrumented with inertial sensors to measure ankle joint kinematics in the field. The purpose of this study was to assess test-retest reliability and concurrent criterion validity of a kinematic assessment using the instrumented soccer equipment. Twelve soccer athletes performed athletic maneuvers in the laboratory and field during 2 sessions. In the laboratory, ankle joint kinematics were simultaneously measured with the instrumented equipment and a conventional motion analysis system. Reliability was assessed using ICC and validity was assessed using correlation coefficients and RMSE. While our design criteria of good test-retest reliability was not supported (ICC > .80), sagittal plane ICCs were mostly fair to good and similar to motion analysis results; and sagittal plane data were valid (r = .90−.98; RMSE < 5°). Frontal and transverse plane data were not valid (r < .562; RMSE > 3°). Our results indicate that the instrumented soccer equipment can be used to measure sagittal plane ankle joint kinematics. Biomechanical studies support the utility of sagittal plane measures for lower extremity injury prevention.
Marion E. Hambrick, Mary A. Hums, Glenna G. Bower and Eli A. Wolff
Elite athletes require the most advanced sports equipment to maintain their competitive edge, but manufacturers cannot always satisfy these athletes’ specific equipment needs. Sport involvement can influence sports-equipment selections and is described as the process by which individuals rely on attitudes and belief systems to make sports-related consumption decisions. This study involved semistructured interviews with 5 elite Parasport athletes to identify and analyze the role of sport involvement in their selection of sports equipment. The results revealed that the athletes identified product limitations, created a collaborative environment, and promoted a culture of innovation to develop new sports products and address existing limitations. Theoretical and practical implications are discussed.
We have developed a 2-D analytical biomechanical model for monoarticular open kinetic-chain exercises with lever selectorized equipment, and different relative placement between the joint center of rotation (J) and the center of rotation (C) of the resistance input lever (“off-center” exercises). All the relevant geometrical aspects of such exercises have been characterized: the change with the joint angle of the distance between the resistance pad (P) and J, and of the angle between CP and JP (i.e., the angle between the resistance input lever and the exercising limb). These changes may strongly affect the joint load and the muscle torque in inverse dynamic problems, given the joint kinematics and the mass of the selected weight stack. Therefore, the muscle torque, the shear and axial components of the joint load have been calculated analytically as a function of the relative positioning of C and J, and the length CP, in addition to the parameters that define the joint kinematics, the equipment mechanics, and the external load. From these results we have derived the optimal cam profiles for “off-center” exercises, as well as the geometrical “off-center” setting that minimizes the shear component of the tibiofemoral joint load in leg extension equipment.
The author derived the exact analytical expression of the instantaneous joint power in exercises with single-joint, variable-resistance, selectorized strength-training equipment, taking into account all the relevant geometric, kinematic, and dynamic variables of both the movable equipment elements (resistance input lever, cam–pulley system, weight stack) and of the user’s exercising limb. A numerical algorithm was also designed to express, in the presence of a cam, the rectilinear kinematic variables of the weight stack as a function of the rotational kinematic variables of the resistance input lever, and vice versa. Given that information, one can measure the value of the instantaneous and mean joint power exclusively by means of a linear encoder placed on the weight stack or, alternatively, only by the use of an angular encoder placed on the rotational axis of the resistance lever. The results highlight that, for knee extension exercises with leg extension equipment, the real values of both instantaneous and mean joint power may differ by more than 50% in comparison with the values obtained by taking into account only the mass and velocity of the weight stack. These differences are notable not only in explosive exercises, but also whenever considerable joint velocities/accelerations occur within the range of motion.
Jennifer L. Huberty, Michael W. Beets, Aaron Beighle, Pedro F. Saint-Maurice and Greg Welk
The purpose of this study was to determine the effectiveness of Ready for Recess, an elementary school recess intervention targeting staff training (ST) or providing recreational equipment (EQ) separately, and the combination (EQ+ST) on physical activity (PA).
Participants were children attending 1 of 12 elementary schools (grades 3rd–6th) included in the study. Separate analytical models were used to evaluate the effects of the intervention conditions on children’s accelerometry and direct observation derived PA measures.
Boys and girls were measured using accelerometry (n = 667). Boys in EQ+ST increased their MVPA by 14.1% while ST decreased their MVPA by –13.5%. Girls in ST decreased their MVPA by –11.4%. Neither boys nor girls in EQ increased their time spent in MVPA. A total of 523 (boys) and 559 (girls) observations were collected. For boys’ and girls’ sedentary and vigorous activity there were no significant main effects for treatment condition, time, or treatment condition-by-time effects.
Environmental modifications are only as strong as the staff that implements them. Supervision, if not interactive, may be detrimental to PA participation, especially in girls. Research related to staff training for encouragement and promotion of PA coupled with appropriate use of equipment during recess is warranted.
Jenna Ratka, Jamie Mansell and Anne Russ
efficacy of preventative strategies. Protective equipment affords the greatest potential for mitigation of injury in full-contact collision sports (e.g., American football, ice hockey). 1 , 4 In some of these sports, helmets and mouthguards are mandated as a strategy to reduce head injuries 5 , 6
Patricia M. Kelshaw, Trenton E. Gould, Mark Jesunathadas, Nelson Cortes, Amanda Caswell, Elizabeth D. Edwards and Shane V. Caswell
during laboratory testing existed at some impact locations and when tested at a low velocity. Only one helmet reached mechanical failure and cracked during performance testing; otherwise, all other helmets met the National Operating Committee on Standards for Athlete Equipment performance requirement. 13
Jennifer L. Copeland, Cheryl Currie, Ali Walker, Erin Mason, Taura N. Willoughby and Ashley Amson
Providing freely accessible exercise facilities may increase physical activity at a population level. An increasingly popular strategy is outdoor fitness equipment in urban parks. Few studies have evaluated the effectiveness of this intervention in smaller cities. This study examined fitness equipment use, perceived effectiveness, and ways to increase use in a city of 100,000 people in 2015.
Two parks with fitness equipment and 4 without were directly observed. Interviews with 139 adults in active parks or living nearby were also conducted.
Only 2.7% of adult park users used the fitness equipment over 100 hours of observation across 3 seasons. In contrast, 22.3% of adults interviewed reported monthly or more use of the equipment, highlighting the limitations of self-report methods. Adults interviewed perceived the equipment as potentially beneficial and suggested strategies to increase public use, including increased advertising, the introduction of programming to teach and encourage use, improved equipment quality, and improved maintenance of the equipment and surrounding area.
In a low density city, park fitness equipment may not be an effective public health practice without additional efforts to market, introduce programming, and maintain these sites.
Shelly K. McCrady-Spitzer, Chinmay U. Manohar, Gabriel A. Koepp and James A. Levine
We tested a low-cost and scalable set of classroom equipment, called Active Classroom Equipment, which was designed to promote physical activity while children learn. We hypothesized the Active Classroom Equipment would be associated with increased physical activity without impairing learning.
Fourteen first-grade students in a public elementary school (7 females, 7 males, aged 6.9 ± (SD) 0.4 years, 24 ± 5.4 kg, BMI 15.8 ± 2.6 kg/m2) used the Active Classroom Equipment for 30 minutes each day throughout the school year. Five-day physical activity was measured using validated triaxial accelerometers at baseline (before the intervention began) and on 4 sequential occasions during the 9-month intervention.
For the baseline period, 5-day physical activity averaged 157 ± 65 AU/min. When the 14 children accessed the Active Classroom Equipment, their mean 5-day physical activity was 229 ± 103 Acceleration Units (AU)/min (P < .0001). There were sequential increases in physical activity over the 9-month intervention (Quarter 1: 163 ± 94 AU/min, Quarter 2: 227 ± 108 AU/min, Quarter 3: 278 ± 61 AU/min, Quarter 4: 305 ± 65 AU/min). Students’ Dynamic Indicators of Basic Early Literacy Skills (DIBELS) scores improved.
Active Classroom Equipment may be one approach to increase physical activity.