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Context: Calculating the resistance provided by elastic resistance is essential with the aim of adjusting the load and controlling the progression of the exercises in programs using elastic resistance. This study aimed (1) to establish a model of the force elongation for CLX bands; (2) to examine whether these models are altered by different aspects of band elongation: the phase of elongation and shortening (concentric and eccentric phases), the elongation speed, and the initial resting length; and (3) to determine the resistance value for 100% of elongation in each color and to compare it with the values reported by Theraband. Design: Cross‐sectional. Methods: Ten CLX bands of each color were elongated by 2 experienced researchers to establish their elongation force curves in series of 10 repetitions per band using a Smith machine for an anchor, examining whether elongation force models were affected by elongation and shortening phases using one 4-loop CLX band stretched to 100% and at 0.50 m/s, elongation speed stretching two 4-loop CLX bands at 0.50 m/s and at 0.70 m/s, and different starting lengths using 3 CLX bands (2, 3, and 4 loops) stretched at 0.50 m/s. Results: No differences were found in the comparisons between phases, speeds, or different start lengths (mean errors ranged from 0.01 [0.07 N] for the blue band to 2.97 [0.94 N] for the gold band). Our values were higher than the reference values provided by Theraband for all colors, ranging from 2.3% to 33.1%. Conclusions: Our findings show that the values provided by the brand underestimate the resistance provided by CLX bands. To solve this, regression equations are provided so professionals can calculate the resistance of CLX bands based on their elongation. In addition, these models are not influenced by the phase of elongation and shortening, the elongation speed, and the initial resting length.

Context: Resistance training with blood flow restriction (BFR) has increased in clinical rehabilitation due to the substantial benefits observed in augmenting muscle mass and strength using low loads. However, there is a great variability of training pressures for clinical populations as well as methods to estimate it. The aim of this study was to estimate the percentage of maximal BFR that could result by applying different methodologies based on arbitrary or individual occlusion levels using a cuff width between 9 and 13 cm. Design: A secondary analysis was performed on the combined databases of 2 previous larger studies using BFR training. Methods: To estimate these percentages, the occlusion values needed to reach complete BFR (100% limb occlusion pressure [LOP]) were estimated by Doppler ultrasound. Seventy-five participants (age 24.32 [4.86] y; weight: 78.51 [14.74] kg; height: 1.77 [0.09] m) were enrolled in the laboratory study for measuring LOP in the thigh, arm, or calf. Results: When arbitrary values of restriction are applied, a supra-occlusive LOP between 120% and 190% LOP may result. Furthermore, the application of 130% resting brachial systolic blood pressure creates a similar occlusive stimulus as 100% LOP. Conclusions: Methods using 100 mm Hg and the resting brachial systolic blood pressure could represent the safest application prescriptions as they resulted in applied pressures between 60% and 80% LOP. One hundred thirty percent of the resting brachial systolic blood pressure could be used to indirectly estimate 100% LOP at cuff widths between 9 and 13 cm. Finally, methodologies that use standard values of 200 and, 300 mm Hg far exceed LOP and may carry additional risk during BFR exercise.

Context: The study purpose was to compare the ankle muscle activation and dynamic ankle joint stability of subjects who underwent endoscopy-assisted Achilles tendon repair (ATR; at ≥ 2 y postsurgery) with age, gender, and activity level-matched healthy control group subjects. Design: Prospective, cross-sectional study. All functional tests were performed on the involved ankle of the ATR group, and at the matched side of healthy age, gender, and activity-level control group subjects. Methods: Fifteen men in each group were evaluated for medial and lateral gastrocnemius, soleus, tibialis anterior, and peroneus longus muscle activation during modified star excursion balance test and heel-rise test performance. The weight-bearing lunge test (ankle dorsiflexion) and heel-rise test distance (ankle plantar flexion) also determined weight-bearing, active ankle mobility magnitudes. The Achilles Tendon Total Rupture Score and Foot and Ankle Outcome Score provided patient-reported outcome perceptions specific to Achilles tendon rupture and comprehensive foot and ankle symptoms and function, respectively. Results: Medial (P = .005) and lateral (P = .012) gastrocnemius displayed greater activation amplitudes in the ATR group during the star excursion balance test, and peroneus longus displayed greater activation amplitudes during the heel-rise test (P = .006). The star excursion balance test reach distance was comparable between groups. Active weight-bearing ankle plantar flexion (heel-rise test) and dorsiflexion (weight-bearing lunge test) mobility magnitudes were lower in the ATR group. Conclusions: Subjects who underwent endoscopy-assisted percutaneous ATR had reduced active weight-bearing ankle dorsiflexion and plantar flexion mobility magnitudes and greater gastrocnemius and peroneus longus neuromuscular activation when performing the same tasks as healthy control group subjects. As surgical approaches evolve to less invasive, soft tissue preserving methods with less tissue morbidity and faster healing, rehabilitation approaches may likewise need to evolve. Level of Evidence: Level III.

Context: Core stability training has been recommended as a vital element in improving movement’s pattern and athletic performance. The main objective of this study was to investigate the effect of 12-week McGill core stability training on movement patterns, shooting accuracy, and throwing performance. Design: Randomized controlled clinical trial. Setting: University research laboratory. Methods: Forty male basketball players were randomly assigned to experimental and control groups. The experimental group completed 12-week McGill core stability training, while the control group completed routine exercise training. Patterns of functional movements was measured through functional movement screen (FMS), shooting accuracy measured by static 3-point shooting (S3P) and dynamic 60-second 3-point shooting test, and throwing performance measured by Functional Throwing Performance Index. Results: Comparison revealed that regardless of received training, after 12 weeks both groups showed significant improvement in all outcome measures. However, experimental group had significantly higher post test scores in FMS (P = .02), S3P (P = .007), and dynamic 60-second 3-point shooting test (P = .01). For Functional Throwing Performance Index, there was no group differences (P = .96). The results of follow-up assessments showed for all measurements including FMS (P = .03), S3P (P = .004), dynamic 60-second 3-point shooting test (P < .001), and Functional Throwing Performance Index (P = .005); experimental group had higher scores than the control group. Conclusions: According to the results, implementing McGill core stability training in basketball routine training would be advisable since significant improvement can be obtained in the measured parameters.

Context: In athletes, postural control impairment and knee muscle dysfunction are the most common disorders following anterior cruciate ligament (ACL) injury. Because of functional changes in the motor cortex following ACL injury, physiotherapy (PT) is not enough for treatment and using neuromodulators, such as trans-cranial direct current stimulation (tDCS) may be necessary. The present study focused on the effects of anodal tDCS (a-tDCS) over the primary motor cortex (M1) concurrent with PT on postural control and muscular performance in the athletes with ACL injury. Design: In this study, 34 athletes with ACL injury were randomly assigned in 2 groups of intervention group (active M1 a-tDCS concurrent with PT, n = 16) and control group (sham M1 a-tDCS concurrent with PT, n = 16). Methods: The participants of all groups received 20-minute 2 mA M1 a-tDCS with PT during 10 sessions, while tDCS was turned off after 30 seconds in the sham group. Before, immediately following, and 1 month after the interventions, the center of pressure and the average of power of flexor and extensor muscles at 2 velocities of 30°/s and 60°/s were measured by force plate and isokinetic devices, respectively. Results: One month after treatment, the displacement of center of pressure was decreased in the intervention group (P < .05), while there were no changes in the control group. Y-axis of center of pressure decreased in the intervention group relative to the control group, although average of power of flexor and extensor muscles increased immediately in both groups, but the rise in the intervention group was larger than that in the control group (P < .05). Conclusion: The findings indicated that M1 a-tDCS can induce the efficacy of PT, which has a lasting effect on the improvement of the postural control in athletes with ACL injury.

Context: After anterior cruciate ligament reconstruction (ACLR), long-term functional deficiencies can occur, with controversial results reported when comparing women and men. Dynamic balance and unilateral hop test performance are considered important indicators for the risk of reinjury of the lower extremity. Although both sexes seem to have a similar risk to experience a second anterior cruciate ligament injury, sex-specific differences of dynamic balance and unilateral hop performance in handball players following ACLR are unknown. Objective: To compare dynamic balance and unilateral hop performance between women and men handball players at least 6 months after ACLR. Design: Cross-sectional pilot study. Participants: Ten women (27.6 [4.5] y) and 10 men (26.5 [3.1] y) handball players 6 to 16 months after ACLR. Outcome Measures: Dynamic balance and unilateral hop performance were assessed using the Y-Balance Test and the Single-Leg Hop for Distance Test. Results: Women players demonstrated significantly better results in the anterior direction of the Y-Balance Test for both legs compared with men players. Hop performance was not significantly different between sexes. Conclusion: Dynamic balance and single-leg hop performance seem not to differ between women and men handball players 6 to 16 months after ACLR. The difference between sexes in the anterior reach direction of the Y-Balance Test should be considered small, rather than representing a true difference.

Context: Typically, most clinical return to activity guidelines recommend that an injured shoulder achieve a 90% to 100% functional performance test limb symmetry index (LSI); however, as previous research demonstrated a 103% to 111% dominant limb bias in seated single-arm shot-put test (SSASPT) performance, the typical criteria might not be appropriate for interpreting SSASPT LSI. Thus, the current objective was to evaluate SSASP LSI differences between dominant and nondominant involved shoulders and to determine how many patients met the suggested 90% to 100% LSI criteria, as well as the 103% for dominant (89% for nondominant) normative SSASPT threshold reported in the literature, at the time of discharge. Design: Cross-sectional. Methods: Patients with shoulder injury or surgery (n = 78) completed the SSASPT at the time of discharge from rehabilitation and were grouped according to whether the involved shoulder was the dominant (n = 42) or nondominant (n = 32) limb. LSI (involved/uninvolved × 100) was computed from the average of 3 SSASPT trial distances completed with each limb. Results: The LSI for the nondominant involved group (88.9% [12.4%]) was significantly less (confidence interval_Diff, −12.1% to −22.1%) than the dominant involved group (106.0% [9.3%]). While 95.2% of patients in the dominant involved group exhibited LSI > 90%, only 43.8% of patients in the nondominant involved group attained LSI > 90%. Across the entire cohort, the odds of a nondominant involved LSI being below the respective SSASPT normative range were 2.04 (95% confidence interval, 0.80–5.21) times higher than the odds of a dominant involved LSI being below the normative range. Conclusions: Patients with dominant limb involvement exhibited higher LSI than patients with nondominant limb involvement at discharge from rehabilitation. Particularly when the nondominant shoulder is involved, these results suggest that patients with shoulder injury and surgery may require longer rehabilitation to attain higher levels of upper-extremity function.

Context: Professional athletes showed excellent results after hip preserving procedures. However, there is still a lack of knowledge regarding the rate of return to activity and the rehabilitation time of recreational athletes. Thus, the aim of this study was to investigate factors that were associated with an extended return-to-activity time in nonprofessional athletes. Design: Retrospective, quantitative case–control study. Methods: This study included 47 cases (45 nonprofessional athletes), which were divided according to return-to-activity time (short term: 0.0–7.0 mo vs long term: >7.0 mo). The clinical outcome were evaluated with the modified Harris hip score, the nonarthritic hip score, the Western Ontario and McMaster Universities Osteoarthritis Index, and the University of California, Los Angeles activity score. For statistical analysis between both groups, an unpaired student t test and a paired Wilcoxon test were used. In addition, the sports behavior, intraoperative findings, and surgical procedures were also assessed. Results: After a mean follow-up of 4.3 years (±0.6; 3.4–5.6), the overall postoperative modified Harris hip score was 81.8 points, the nonarthritic hip score was 75.8 points, the Western Ontario and McMaster Universities Osteoarthritis Index was 36.7 points, and the University of California, Los Angeles activity score was 7.9. Compared with the preoperative results, all scores improved significantly (P < .001). Patients of the short-term return-to-activity group showed a higher preoperative activity diversity and, postoperatively, a higher rate in high-impact sports (P = .024). Conclusions: After mini-open arthrotomy for femoroacetabular impingement syndrome treatment, 92.5% of the recreational athletes returned to sports activity. The findings did not detect factors influencing the return-to-activity time. However, a higher preoperative diversity of activities and a shift to high-level impact sport activities might support a shorter rehabilitation.