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Javad Sarvestan, Alan R. Needle, Peyman Aghaie Ataabadi, Zuzana Kovačíková, Zdeneˇk Svoboda and Ali Abbasi

Context: Chronic ankle instability is documented to be followed by a recurrence of giving away episodes due to impairments in mechanical support. The application of ankle Kinesiotaping (KT) as a therapeutic intervention has been increasingly raised among athletes and physiotherapists. Objectives: This study aimed to investigate the impacts of ankle KT on the lower-limb kinematics, kinetics, dynamic balance, and muscle activity of college athletes with chronic ankle instability. Design: A crossover study design. Participants: Twenty-eight college athletes with chronic ankle sprain (11 females and 17 males, 23.46 [2.65] y, 175.36 [11.49] cm, 70.12 [14.11] kg) participated in this study. Setting: The participants executed 3 single-leg drop landings under nontaped and ankle Kinesio-taped conditions. Ankle, knee, and hip kinematics, kinetics, and dynamic balance status and the lateral gastrocnemius, medial gastrocnemius, tibialis anterior, and peroneus longus muscle activity were recorded and analyzed. Results: The application of ankle KT decreased ankle joint range of motion (P = .039) and angular velocities (P = .044) in the sagittal plane, ground reaction force rate of loading (P = .019), and mediolateral time to stability (P = .035). The lateral gastrocnemius (0.002) and peroneus longus (0.046) activity amplitudes also experienced a significant decrease after initial ground contact when the participants’ ankles were taped, while the application of ankle KT resulted in an increase in the peroneus longus (0.014) activity amplitudes before initial ground contact. Conclusions: Ankle lateral supports provided by KT potentially decreases mechanical stresses applied to the lower limbs, aids in dynamic balance, and lowers calf muscle energy consumption; therefore, it could be offered as a suitable supportive means for acute usage in athletes with chronic ankle instability.

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Kaitlin M. Gallagher, Anita N. Vasavada, Leah Fischer and Ethan C. Douglas

A popular posture for using wireless technology is reclined sitting, with the trunk rotated posteriorly to the hips. This position decreases the head’s gravitational moment; however, the head angle relative to the trunk is similar to that of upright sitting when using a tablet in the lap. This study compared cervical extensor musculotendon length changes from neutral among 3 common sitting postures and maximum neck flexion while using a tablet. Twenty-one participants had radiographs taken in neutral, full-flexion, and upright, semireclined, and reclined postures with a tablet in their lap. A biomechanical model was used to calculate subject-specific normalized musculotendon lengths for 27 cervical musculotendon segments. The lower cervical spine was more flexed during reclined sitting, but the skull was more flexed during upright sitting. Normalized musculotendon length increased in the reclined compared with an upright sitting position for the C4-C6/7 (deep) and C2-C6/7 (superficial) multifidi, semispinalis cervicis (C2-C7), and splenius capitis (Skull-C7). The suboccipital (R 2 = .19–.71) and semispinalis capitis segment length changes were significantly correlated with the Skull-C1 angle (0.24–0.51). A semireclined reading position may be an ideal sitting posture to reduce the head’s gravitational moment arm without overstretching the assessed muscles.

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Catalina Belalcazar and Bettina Callary

The purpose of this article is to describe the evolution and influence of Masters Player-Coaches (MPCs) in the Asociación de Futbolistas Adultos Mayores del Tolima (in English: Masters Athletes’ Football Association of Tolima in Colombia, South America), a football league for men aged 60–70+ years. Historical forces shape a cultural backdrop that pervades football (soccer) and coaching and provides an understanding of how MPCs perceive themselves. After exploring the evolution and influence of the league, the authors uncover a peer-coaching approach in Asociación de Futbolistas Adultos Mayores del Tolima, described by the MPCs as Compañero Orientador. The authors link the importance of formally acknowledging the MPCs with their influence in fighting ageism, community building, and promoting lifelong sport. Further, MPCs provide high-quality Masters sport experiences, and their recognition supports a formal sporting structure in applying for local government grants to support the growing Masters context in Colombia.

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Banu Unver, Kartal Selici, Eda Akbas and Emin Ulas Erdem

The purpose of the study was to investigate the foot posture, ankle muscle strength, range of motion (ROM), and plantar sensation differences among normal weight, overweight, and obese individuals. One hundred and twenty-three individuals (42 normal weight, 40 overweight, and 41 obese) aged between 18 and 50 years participated in the study. Foot posture, ankle muscle strength, ROM, plantar sensation, and foot-related disabilities were evaluated. The relative muscle strength of left plantar flexors and invertors and light touch sensation of the left heel were significantly lower in obese individuals compared with overweight and normal weight (P < .016) individuals. Obese individuals had significantly reduced relative muscle strength of plantar flexors, dorsiflexor, and invertors, plantar flexion and inversion ROM in the left foot; and light touch sensation of the right heel compared with normal weight (P < .016) individuals. Foot Posture Index scores were significantly higher in obese individuals compared with overweight (P < .016) individuals. There were no significant differences in absolute muscle strength, vibration sensation, and foot-related disability scores among the 3 groups (P > .05). Obesity was found to have adverse effects on ankle muscle strength, ROM, and plantar light touch sensation. Vibration sensation was not affected by body mass index, and foot-related disability was not observed in obese adults.

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Dean Barker, Mikael Quennerstedt, Anna Johansson and Peter Korp

Aim: To provide insight into how physical education teachers use discursive resources related to obesity to create particular professional identities. Method: Data come from focus group and individual interviews with physical education teachers in Sweden. Discourse theory on teacher identities frame the analysis of the empirical material. Results: Data suggest that teachers in Sweden make use of six distinct but related discursive contributions to produce three professional identities: the caring practitioner, an identity concerned with ensuring all pupils irrespective of size participate in physical education; the activity luminary, an identity that focuses on inspiring pupils toward activity across the lifespan, and; the body rationalist, an identity concerned with challenging unrealistic media discourses and reassuring pupils that they have “normal” bodies. Discussion: The identities appear more inclusive, sensitive, and critical than current physical education literature on obesity suggests, however they also contain elements that are fundamentally unsympathetic to overweight individuals.

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Caleb D. Johnson and Irene S. Davis

Higher medial–lateral forces have been reported in individuals with stiffer foot arches. However, this was in a small sample of military personnel who ran with a rearfoot strike pattern. Therefore, our purpose was to investigate whether runners, both rearfoot and forefoot strikers, show different associations between medial–lateral forces and arch stiffness. A group of 118 runners (80 rearfoot strikers and 38 forefoot strikers) were recruited. Ground reaction force data were collected during running on an instrumented treadmill. Arch flexibility was assessed as the difference in arch height from sitting to standing positions, and participants were classified into stiff/flexible groups. Group comparisons were performed for the ratio of medial:vertical and lateral:vertical impulses. In rearfoot strikers, runners with stiff arches demonstrated significantly higher medial:vertical impulse ratios (P = .036). Forefoot strikers also demonstrated higher proportions of medial forces; however, the mean difference did not reach statistical significance (P = .084). No differences were detected in the proportion of lateral forces between arch flexibility groups. Consistent with previous findings in military personnel, our results indicate that recreational runners with stiffer arches have a higher proportion of medial forces. Therefore, increasing foot flexibility may increase the ability to attenuate medial forces.

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Tyler N. Brown, AuraLea C. Fain, Kayla D. Seymore and Nicholas J. Lobb

This study determined changes in lower limb joint stiffness when running with body-borne load, and whether they differ with stride or sex. Twenty males and 16 females had joint stiffness quantified when running (4.0 m/s) with body-borne load (20, 25, 30, and 35 kg) and 3 stride lengths (preferred or 15% longer and shorter). Lower limb joint stiffness, flexion range of motion (RoM), and peak flexion moment were submitted to a mixed-model analysis of variance. Knee and ankle stiffness increased 19% and 6% with load (P < .001, P = .049), but decreased 8% and 6% as stride lengthened (P = .004, P < .001). Decreased knee RoM (P < .001, 0.9°–2.7°) and increased knee (P = .007, up to 0.12 N.m/kg.m) and ankle (P = .013, up to 0.03 N.m/kg.m) flexion moment may stiffen joints with load. Greater knee (P < .001, 4.7°–5.4°) and ankle (P < .001, 2.6°–7.2°) flexion RoM may increase joint compliance with longer strides. Females exhibited 15% stiffer knee (P = .025) from larger reductions in knee RoM (4.3°–5.4°) with load than males (P < .004). Stiffer lower limb joints may elevate injury risk while running with load, especially for females.