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This study aimed to explain how injured athletes high in hardiness experienced stress-related growth (SRG) and why athletes low in hardiness are less likely to derive such benefits. Twenty participants were theoretically sampled into high (N=10) and low (N=10) hardiness groups. Semi-structured interviews were used for data collection. Findings revealed that athletes high in hardiness experienced SRG from having an emotional outlet, which enabled them to reframe their injury and experience positive affect. In contrast, athletes low in hardiness had no emotional outlet, which led to sub-optimal outcomes. These findings have important implications for practitioners working with injured athletes.

1This study examined the relationship between hardiness, coping and perceived stress-related 2 growth (SRG) in a sport injury context. Due to the exploratory nature of the study, a cross-3 sectional design was employed, whereby 206 previously injured athletes (148 male, 58 4 female, M age = 22.23 years) who had recently returned to sport completed three 5 questionnaires: Dispositional Resilience Scale, Stress-Related Growth Scale, and Brief 6 COPE. Pearson product-moment correlations and Preacher's and Hayes's (2008) 7bootstrapping procedure were used to analyze the data. Findings revealed a significant 8 positive relationship between hardiness and perceived SRG (r = .36; p < .05). Two coping 9 strategies were found to mediate this relationship (i.e., emotional support and positive 10 reframing). That is, the reason why athletes higher in hardiness had higher SRG scores is 11 because they reported greater use of their social support for emotional reasons (e.g., moral 12 support, sympathy or understanding) and were able to construe their injury in positive terms. 13 These findings support some of the central tenets of Joseph and Linley's (2005) organismic 14 valuing theory and provides implications for professional practice. Future researchers should 15 embrace qualitative inquiry to enhance the interpretability and meaningfulness of these 16 findings (e.g., interpretative phenomenological analysis, narrative analysis), and use a 17 prospective, longitudinal pre-to-post sport injury design to further substantiate them.18 19

Background: We aimed to determine if a shock absorbing pylon (SAP) influenced the ground reaction force characteristics and the shock absorbing mechanisms compared to a rigid pylon (Rigid) during the loading phase in running. Objectives: To determine if the SAP influences the mechanisms of loading compared to the Rigid condition. Study Design: A convenience sample of transtibial amputees participated in a laboratory-based study. The prosthetic set-up was randomly altered fd\sdsd. Methods: Five recreationally active male transtibial amputees age: 18-50 years; mean mass: 86.7 ± 17.5 kg; height: 1.77 ± 0.07 m) volunteered from a population-based sample. They completed a within-participant-designed study assessing a SAP and a Rigid condition during running. Kinematic and kinetic data were collected during two sessions following a one-week customization period. Results: Loading rate, peak vertical and horizontal ground reaction forces and the time to each measure along with knee and hip angular displacement, absorbing powers and work done between the SAP and Rigid conditions were not systematically affected by the prosthetic condition. Conclusions: The effect of the SAP was minimal and inconsistent in the loading phase, with only some amputees presenting higher and others with lower values for the tested variables. Clinical relevanceThe inclusion of a prosthetic shock absorber in the form of a SAP did not systematically alter the kinetic characteristics or shock absorbing mechanisms of the residual joints. It appears that the prescription of a SAP is not justified for these recreationally active amputees.

Objectives: To investigate the effect of progressive whole-body hyperthermia on maximal, and rapid voluntary torque production, and their neuromuscular determinants. Design: Repeated measures, randomised. Methods: Nine participants performed sets of neuromuscular assessments in HOT conditions (∼50 • C, ∼35% relative humidity) at rectal temperatures (T re ) of 37, 38.5 and 39.5 • C and in CON conditions (∼22 • C, ∼35% relative humidity) at a T re of ∼37 • C and pre-determined comparative time-points. Electrically evoked twitch (single impulse) and octet (8 impulses at 300 Hz) responses were measured at rest. Maximum voluntary torque (MVT), surface electromyography (EMG) normalised to maximal M-wave, and voluntary activation (VA) were measured during 3−5 s isometric maximal voluntary contractions. Rate of torque development (RTD) and normalised EMG were measured during rapid voluntary isometric contractions from rest. Results: All neuromuscular variables were unaffected by time in CON. In HOT, MVT, normalised EMG at MVT and VA were lower at 39.5 • C compared to 37 • C (p < 0.05). Early-(0−50 ms) and middle-(50−100 ms) phase voluntary RTD were unaffected by increased T re (p > 0.05), despite lower normalised EMG at T re 39.5 • C (p < 0.05) in rapid contractions. In contrast, late-phase (100−150 ms) voluntary RTD was lower at 38.5 • C and 39.5 • C compared to 37 • C (p < 0.05) in HOT. Evoked twitch and octet RTD increased with increased T re (p < 0.05). Conclusions: Hyperthermia reduced late-phase voluntary RTD, likely due to reduced neural drive and the reduction in MVT. In contrast, early-and middle-phase voluntary RTD were unaffected by hyperthermia, likely due to the conflicting effects of reduced neural drive but faster intrinsic contractile properties.

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This study investigated vertical jumps from single support for two trans-tibial amputees from a standing position. The mechanisms used to achieve flight and the compensatory mechanisms used in the production of force in the absence of plantarflexors are detailed. Two participants completed countermovement maximum vertical jumps from the prosthetic and the sound limbs. The jumps were recorded by a 7-camera 512 VICON motion analysis system integrated with a Kistler forceplate. Flight height was 5 cm jumping from the prosthetic side and 18 -19 cm from the sound side. The countermovement was shallower and its duration was less on the prosthetic side compared to the sound side. The reduced and passive range of motion at the prosthesis resulted in an asymmetrical countermovement for both participants with the knee and ankle joints most affected. The duration of the push-off phase was not consistently affected. At take-off the joints on the sound side reached close to full extension while on the prosthetic side they remained more flexed. Joint extension velocity in the push-off phase was similar for both participants on the sound side, though the timing for participant 2 illustrated earlier peaks. The pattern of joint extension velocity was not a smooth proximal to distal sequence on the prosthetic side. The magnitude and timing of the inter-segment extensor moments were asymmetrical for both subjects. The power pattern was asymmetrical in both the countermovement and push-off phases; the lack of power generation at the ankle affected that produced at the remaining joints.

A unilateral transtibial amputation causes a disruption to the musculoskeletal system, which results in asymmetrical biomechanics. The current study aimed to assess the movement asymmetry and compensations that occur as a consequence of an amputation when performing a countermovement vertical jump. Six unilateral transtibial amputees and 10 able-bodied (AB) participants completed 10 maximal vertical jumps, and the highest jump was analyzed further. Three-dimensional lower limb kinematics and normalized (body mass) kinetic variables were quantified for the intact and prosthetic sides. Symmetry was assessed through the symmetry index (SI) for each individual and statistically using the Mann-WhitneyUtest between the intact and prosthetic sides for the amputee group. A descriptive analysis between the amputee and AB participants was conducted to explore the mechanisms of amputee jumping. The amputee jump height ranged from 0.09 to 0.24 m. In the countermovement, all ankle variables were asymmetrical (SI > 10%) and statistically different (p< .05) for the amputees. At the knee and hip, there was no statistical difference between the intact and prosthetic sides range of motion, although there was evidence of individual asymmetry. The knees remained more extended compared with the AB participants to prevent collapse. In propulsion, the prosthesis did not contribute to the work done and the ankle variables were asymmetrical (p< .05). The knee and hip variables were not statistically different between the intact and prosthetic sides, although there was evidence of functional asymmetry and the contribution tended to be greater on the intact compared with the prosthetic side. The lack of kinetic involvement of the prosthetic ankle and both knees due to the limitation of the prosthesis and the altered musculoskeletal mechanics of the joints were the reason for the reduced height jumped.