Objective: To validate and evaluate the intra- and inter-rater reliability of the 2-min step test (2MST) in measuring the functional performance of patients with knee pain associated with osteoarthritis (OA). Methods: Forty-one patients with knee OA was included. Two examiners assessed the patients at two times with interval between the test and retest from 7 to 14 days. All executions of 2MST were recorded in real time by the examiners and were also recorded by video. The intraclass correlation coefficient (ICC) and 95% confidence interval (CI), standard error of measurement (SEM) and minimum detectable difference (MDD) were used to determine reliability. In the construct validity, we correlate the score of the 2MST with the other instruments used in the study: The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Numerical Pain Scale (NPS), Pain-Related Catastrophizing Thoughts Scale (PCTS) and Chronic Pain Self-Efficacy Scale (PSEQ). The agreement between the face-to-face assessment and the evaluation based on the video record was assessed using the Bland-Altman methodology in the 4 moments of the 2MST. Results: 2MST presented excellent intra- (ICC = 0.94, SEM = 4.47, MDD = 12.40) and inter-rater reliability (ICC = 0.97, SEM = 3.07, MDD = 8.52). The agreement was acceptable between face-to-face assessments and the analyzes performed on video. All instruments showed a statistically significant correlation with 2MST, except the PCTS. A correlation magnitude above 0.50 was found between the 2MST and pain and function domains of the WOMAC, and a correlation magnitude between 0.30 and 0.50 with the joint stiffness domain of the WOMAC, NRPS and PSEQ. Conclusion: 2MST proved to be valid for assessing functional capacity in patients with knee OA, with excellent reliability.

Purpose: To analyze the muscle activation of the rectus femoris (RF), vastus lateralis (VL), gluteus maximus (GM), and biceps femoris (BF) in concentric and eccentric actions in the squat at 90° and 140° range of motion. Methods: Thirty-five women (32.9 ± 7.4 years; 64.5 ± 11.5 kg; 1.63 ± 0.1 m; BMI: 24.2 ± 2.9 kg/m²; %fat: 24.9 ± 6.5%) experienced exercise for at least eight weeks. Electrodes were positioned in standardized locations. The signals were acquired by an A/D SAS1000 V8 converter and the electromyographic activity normalized in the percentage of the highest produced value (%RMS). The data were analyzed using repeated measures two-way ANOVA, with effect size (η²) and differences calculated in percentage points (∆ p.p.). Results: The RF (p = 0.001; ∆ = 5.1 p.p.) and BF activation (p = 0.020; ∆ = 4.0 p.p.) was higher at 90° in the eccentric action. The RF showed an interaction between the range of motion and %RMS, with a large effect size (F = 37.9; p = 0.001; η² = 0.485). The VL activation was higher at 140° (p = 0.005; ∆ = 3.9 p.p.) in the concentric action and higher at 90° (p = 0.006; ∆ = 3.7 p.p.) in the eccentric action, with a large effect size significant interaction (F = 21.3; p = 0.001; η² = 0.485). The GM activation was higher at 90° in the concentric (p = 0.020; ∆ = 5.4 p.p.) and eccentric action (p = 0.022; ∆ = 41 p.p.). Conclusions: The biarticular muscles were influenced by the squat range only in the eccentric action of the movement, while the monoarticular muscles were influenced by the squat in both concentric and eccentric muscle action.

Women’s participation in soccer has increased rapidly. The purpose of this study was to evaluate the physiological demands imposed on women’s NCAA Division I soccer players across a season according to speed, total distance traveled, and numbers of sprints measured via GPS (Polar Team Pro^®). Eighteen athletes (19.2 ± 1.1 years, 50.5 ± 6.5 mL/kg/min and 23.4 ± 3.6% fat) participated in this study. The analysis was obtained through 13 official matches. Speed zones were defined as Zone 1 (1.0 to 5.99 km·h⁻¹), Zone 2 (6.0 to 10.99 km·h⁻¹), Zone 3 (11.0 to 15.49 km·h⁻¹), Zone 4 (15.5 to 19.9 km·h⁻¹) and Zone 5 (sprint > 20 km·h⁻¹), with Zones 4–5 considered as high intensity running. Individual differences in playing time and total distance were highly variable due to substitutions. Average distance traveled per game in quartiles was 3.9 km, 5.6 km and 7.4 km in the 25th, 50th, and 75th quartiles, respectively. Relative to playing time, players travelled an average of 113.64 ± 17.12 m/min (range: 93.7 to 143.5 m/min) and ran one sprint every 4.12 ± 2.06 min. When distance was summated and analyzed for the entire team, significant difference between halves was found for speed Zones 2, 3 and 4, with greater values found in the first half. Total distance, high intensity running and sprint distance were significantly less than previously recorded in professional players. These findings suggest that coaches should consider the unique physiological demands and recovery opportunities present in NCAA play when constructing practices and conditioning programs.

This study compared the exercise intensity of four specific soccer training sessions (friendly and training match, tactical and technical workouts). Ten professional soccer players (24.2 ± 3.7 years, 177.9 ± 7.3 cm, 63.2 ± 4.6 mLO2•kg-1•min-l) were recruited. A treadmill progressive interval test was performed to determine the players' VO2max, maximal heart rate (HRmax), HR-VO2 curve, and the heart rate corresponding to blood lactate concentrations of 2 and 4 mmol/L. The heart rate during the training sessions was used to estimate the exercise intensity and to classify them into intensity zones (low-intensity: 4 mmol/L). Exercise intensities were different among training sessions (friendly match: 86.0 ± 5.1% HRmax; training match: 81.2 ± 4.1% HRmax; tactical workout: 70.4 ± 5.3% HRmax; technical workout: 62.1 ± 3.6% HRmax). The friendly match presented the highest percentage of time performed in the high-intensity zone.