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This study aimed to evaluate whether lifting velocity can be used to estimate the overhead press one repetition maximum (1RM) and to explore the differences in the accuracy of the 1RM between three velocity-based methods. Twenty-seven weightlifters (16 men and 11 women) participated. The first session was used to test the overhead press 1RM. The second session consisted of an incremental loading test during the overhead press. The mean velocity was registered using a transducer attached to the barbell. A 1-way repeated-measures analysis of variance (ANOVA) with Bonferroni post hoc corrections was applied to the absolute differences between the actual and predicted 1RMs. Raw differences with 95% limits of agreement and ordinary least-products regressions were used to test the concurrent validity of the 1RM prediction methods with respect to the actual 1RM. The ANOVA did not reveal significant differences for the absolute differences respect to the actual 1RM between the three 1RM prediction methods ( F = 3.2, p = .073). The absolute errors were moderate for the Multiple-Point (6.1 ± 3.7%), Two-Point45−75 (8.6 ± 6.2%), and Two-Point45−90 methods (5.7 ± 4.0%). The validity analysis showed that all the 1RM prediction methods underestimated the actual 1RM (1.0–2.2 kg), but ordinary least-products regressions failed to show fixed or proportional bias. These results suggest that the Multiple-Point and Two-Point45−90 velocity-based methods might be viable tools to predict the overhead press 1RM in weightlifters, but practitioners are encouraged to use the direct 1RM for a more accurate prescription of the training loads.

Objectives\ud Guidelines for a comprehensive rehabilitation programme for patellofemoral pain (PFP) have been developed by international experts. The aim of this study was to analyse the effect of such a rehabilitative exercise programme on pain, function, kinesiophobia, running biomechanics, quadriceps strength and quadriceps muscle inhibition in individuals with PFP.\ud \ud Design\ud Observational study.\ud \ud Setting\ud Clinical environment.\ud \ud Participants\ud Twenty-seven participants with PFP.\ud \ud Main outcome measures\ud Symptoms [numeric pain rating scale (NPRS)and the pain subscale of the Knee Injury and Osteoarthritis Outcome Score (KOOS)], function measured by using the KUJALA scale and KOOS, kinesiophobia measured by using the Tampa scale, three-dimensional biomechanical running data, quadriceps isometric, concentric and eccentric strength and arthrogenic muscle inhibition (AMI) were acquired before and after the six-week exercise programme.\ud \ud Results\ud Although pain did not significantly improve all patients were pain-free after the six-week exercise programme (NPRS: p = 0.074). Function, kinesiophobia and quadriceps AMI improved significantly after the six-week exercise programme (KUJALA: p = 0.001, KOOS: p = 0.0001, Tampa: p = 0.017, AMI: p = 0.018). Running biomechanics during stance phase did not change after the exercise intervention. Quadriceps strength was not different after the six-week exercise programme (isometric: p = 0.992, concentric: p = 0.075, eccentric: p = 0.351).\ud \ud Conclusion\ud The results of this study demonstrate that the current exercise recommendations can improve function and kinesiophobia and reduce pain and AMI in individuals with PFP. There is a need for reconsideration of the current exercise guidelines in stronger individuals with PFP.

Context:Injuries to the anterior cruciate ligament (ACL) and patellofemoral joint (PFJ) are a significant problem in female athletes. A number of screening tasks have been used in the literature to identify those at greatest risk of injury. To date, no study has examined the relationship in 2-dimensional (2D) knee valgus between common screening tasks to determine whether individuals exhibit similar movement patterns across tasks.Objective:To establish whether frontal-plane projection angle (FPPA) during the single-leg squat (SLS), single-leg land (SLL), and drop jump (DJ) are related.Design:Cross-sectional study.Setting:University laboratory.Participants:52 national-league female football players and 36 national-league female basketball players.Main Outcome Measures:2D FPPA during the SLS, SLL, and DJ screening tasks.Results:Significant correlations were found between tasks. FPPA in the SLS was significantly correlated with SLL (r = .52) and DJ (r = .30), whereas FPPA in the SLL was also significantly correlated to DJ (r = .33). FPPA was significantly greater in the SLS than in the SLL (P < .001) and DJ (P < .001) and in the SLL than in the DJ (P < .001).Conclusion:The results showed that 2D FPPA is correlated across the SLS, SLL, and DJ tasks. However, significantly greater FPPA values in the unilateral tasks suggest that the DJ may not identify risk of injury in sports where primary injury mechanisms are during unilateral loading tasks. Therefore, it is recommended that both unilateral and bilateral tasks be included when screening for ACL and PFJ injury risk.

The purpose of this study was to investigate the mechanical similarity between net joint moments (NJM) of the countermovement jump (CMJ) and the hang power clean (HPC) and jump shrug (JS). Twelve male Lacrosse players performed three maximal effort CMJs and three repetitions of the HPC and JS at 30%, 50%, and 70% of their HPC one repetition maximum (1-RM). Ground reaction forces and motion capture data were used to calculate the NJM of the hip, knee, and ankle joints during each exercise. Statistical comparison of the peak NJM indicated that NJM during the HPC and JS across all loads were equal to or greater than the NJM during the CMJ (all p < 0.025). In addition, correlation analyses indicated that CMJ hip NJM were associated (all p < 0.025) with HPC hip NJM at 30% and 70% (r = 0.611-0.822) and JS hip NJM at 50% and 70% (r = 0.674-0.739), whereas CMJ knee NJM were associated with HPC knee NJM at 70% (r = 0.638) and JS knee NJM at 50% and 70% (r = 0.664-0.732). Further, CMJ ankle NJM were associated with HPC ankle NJM at 30% and 50% (r = 0.615-0.697) and JS ankle NJM at 30%, 50%, and 70% (r = 0.735-0.824). Lastly, knee and ankle NJM during the JS were greater than during the HPC at 30% and 50% of 1-RM (all p < 0.017). The degree of mechanical similarity between the CMJ and the HPC and JS is dependent on the respective load and joint. [Abstract copyright: © Journal of Sports Science and Medicine.]