Background Achilles tendon disorders are very common among athletes. It is important to measure symptoms and functional limitations objectively related to Achilles tendinopathy using outcome measures that have been validated in the language of the target population. Objectives To perform a cross-cultural adaptation and to evaluate the measurement properties of the Brazilian version of the Victorian Institute of Sport Assessment-Achilles (VISA-A) questionnaire. Methods This clinical measurement study adapted the VISA-A questionnaire to Brazilian Portuguese (VISA-A-Br). The adapted questionnaire was then tested on 2 occasions within an interval of 5 to 14 days. This study evaluated the following measurement properties: internal consistency, test-retest reliability, measurement error, construct validity, and ceiling and floor effects. Results The VISA-A-Br showed good internal consistency (Cronbach α = .79; after excluding 1 item at a time, Cronbach α = .73-.84), good test-retest reliability (intraclass correlation coefficient model 2,1 = 0.84; 95% confidence interval: 0.71, 0.91), an acceptable measurement error (standard error of measurement, 3.25 points; smallest detectable change, 9.02 points), good construct validity (Spearman correlation coefficients for the Lower Extremity Functional Scale, 0.73; the Foot and Ankle Outcome Score pain subscale, 0.66; other symptoms subscale, 0.48; function in daily living subscale, 0.59; function in sport and recreation subscale, 0.67; and foot and ankle- related quality of life subscale, 0.70), and no ceiling and floor effects. Conclusion The clinical measurement properties of the VISA-A-Br are equivalent to those of the original version, and the instrument has been validated and confirmed as reliable to measure pain and function among the Brazilian population with Achilles tendinopathy. This adaptation of the questionnaire may be used in clinical and scientific settings. J Orthop Sports Phys Ther 2018;48(7):567-573. Epub 24 Apr 2018. doi:10.2519/jospt.2018.7897.

ABSTRACT:Objectives: The purpose this study was to investigate the effects of different vascular occlusion levels (total occlusion (TO), partial occlusion (PO) or free flow (FF)) during intermittent isometric handgrip exercise (IIHE) on the time to failure (TF) and the recovery of the maximum voluntary isometric force (MVIF), median frequency (EMGFmed) and peak of EMG signal (EMGpeak) after task failure. Methods: Thirteen healthy men (21 ± 1.71 year) carried out an IIHE until the failure at 45% of MVIF with TO, PO or FF. Occlusion pressure was determined previously to the exercise. The MVIF, EMGFmed and EMGpeak were measured before and after exercise. Results: TF was significantly different (p < 0.05) among all investigated conditions: TO (150 ± 68s), PO (390 ± 210s) and FF (510 ± 240s). The MVIF was lower immediately after IIHE, remaining lower eleven minutes after failure in all cases (p <0.05), when compared to pre exercise. There was a greater force reduction (p <0.05) one minute after the failure in the PO (-45.8%) and FF (-39.9%) conditions, when compared to TO (-28.1%). Only the PO condition induced lower MVIF (p <0.05) than in the TO, eleven minutes after the task failure. PO induced a greater reduction in EMGFmed compared TO and greater increase in EMGpeak, when compared to TO and FF (p <0.05). Conclusions: TO during IIHE lead to a lower time to failure, but a faster MVIF recovery, while the PO seems to be associated to a slower neuromuscular recovery, when compared to other conditions.

Background. Low-intensity exercise with blood flow restriction (BFR) may improve muscle mass and strength but an early neuromuscular fatigue may occur. Since the mechanisms of fatigue during BFR exercise is not yet fully understood we examined, concomitantly, the coefficient of variation of force (CVf) and surface electromyographic signal (sEMG) during an intermittent isometric handgrip exercise (IIHE) taken to failure. Methods. 12 males completed an IIHE to failure with three blood flow conditions: total BFR (TR), partial BFR (PR) and free blood flow (FF). At each condition, three moments of the task were identified: beginning, midway and failure. The CVf and amplitude of rectified (arEMG) and median frequency (MDF) from the sEMG were analyzed. Results. FF and PR conditions presented similar increase throughout the entire task in CVf (FF=1.73±0.88%; PR=1.61±0.63%) and arEMG (FF=1.48±0.63%; PR=1.40±0.45%), and similar decrease in MDF (FF=0.88±0.16%; PR=0.88±0.14%). Differently, during the task with TR there was a significant increase in CVf (1.45±0.79%) and arEMG (1.27±0.40%) and decrease in MDF (0.85±0.19%) only at the failure. The comparisons between conditions showed that the CVf, arEMG, and MDF were significantly lower (p<0.05) at TR condition, when compared to the FF. Conclusions. Simultaneous analysis of CVf and sEMG indicates that FF and PR conditions induce similar neuromuscular fatigue during an IIHE, while the adjustments to maintain the task are different in TR. Additionally, it does not seem necessary to add a partial BFR to increase muscle excitation during an exercise taken to failure.

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The aim of this study was to evaluate the effect of swimming exercise, without overloading, on the biomechanical parameters of the calcaneal tendon of rats. 27 male Wistar rats (70 days) were distributed randomly into 2 groups, Control Group (CG; n=15) with restricted movements inside the cage and Swimming Group (SG; n=12), subjected to exercise training in a tank with a water temperature of 30±1°C, for 1 h/day, 5 days/week for 8 weeks. All animals were kept in a reversed light/dark cycle of 12 h with access to food and water ad libitum. After that, they were anesthetized and had their calcaneus tendons collected from their left rear paws. The tendon was submitted to a mechanical test on a conventional test machine. From the stress vs. strain curve, the biomechanical data were analyzed. For the statistical analysis, the Student-T test was used (p<0.05). Of the variables examined, the maximum tension (p=0.009), maximum force (p=0.03), energy of deformation/tendon cross sectional area (p=0.017) and elastic modulus of the tendon (p=0.013) showed positive outcomes in SG. There was no difference in the other parameters. The results indicate that the swimming exercise training, without overloading, was an important stimulus for improving the biomechanical parameters and structural properties of the calcaneal tendon.