George Mavrommatis

Muscle fatigue is a critical factor influencing athletic performance in soccer. The aim of the present study was to investigate changes in isokinetic torque and power of lower limbs, in young female soccer players, in training microcycle of competitive season. The sample consisted of eleven female soccer players U17 (age: 16.3 ± 0.8 years, height: 166.4 ± 6.4 cm, body weight: 64.7 ± 11.7 kg) who competed in the 3rd national division championship. Participants knee extensors/flexors muscles were assessed in three concentric angular speeds (60°/s, 180°/s, 300°/s) and in counter movement jump, 72 hours before 24, 48 and 72 hours after the match. Statistically significant differences were revealed (F = 5,681, p = 0.038) in isokinetic assessment. Extensors significantly decreased at 60°/s between initial measurements and 48 hours after the match (p = 0.008), as well as 48 to 72 hours postmatch (p = 0.017). Flexors significantly decreased between the measurements at 24 to 48 hours at 300°/s (p = 0.025). Analysis of the Counter Movement Jump (CMJ) data revealed that both CMJ with and without arm swing had no statistically significant differences in performance between all four measurements. Knee muscles isokinetic assessment is a sensitive method for detecting post-match muscle fatigue. Structuring of training microcycle should consider the recovery time-lines and the physiological characteristics of female soccer players to optimize performance.

This study compared the five most commonly used equations for calculating gait symmetry in discrete variables among Parkinson’s disease patients. Twelve patients (five women and seven men) performed ten consecutive gait trials on a 10 m walkway. Gait data were collected using eight optoelectronic cameras (100 fr/s). The analysis focused on various spatiotemporal parameters, including cadence, step time, stride time, single support, double support, walking speed, step length, stride length, step width, and foot angle. Five symmetry indices were calculated for each trial rather than averaging the ten recorded trials. The variability in and reliability of each symmetry equation were assessed using the coefficient of variation (CV) and intraclass correlation coefficient (ICC), respectively. Additionally, Bland–Altman plots were produced to visualize the agreement between each pair of methods for each spatiotemporal parameter. The results revealed that the symmetry ratio method exhibited lower variability and higher reliability compared with the other four indices across all spatiotemporal gait parameters. However, it was found that the reliability of a single trial was generally poor, regardless of the symmetry calculation formula used. Therefore, we recommend basing measurements of gait asymmetry in Parkinson’s disease on multiple trials.

The aim of this study was to apply a training plan to four different-length microcycles (MIC) in soccer and analyze (a) the load within the training weeks and (b) the short-term effect on the matches that were played at the end of each microcycle. An intervention training program applied to microcycles of five, six, seven and nine days during two seasons of the Cypriot Fist Division. The GPS technology and subjective (wellness, RPE) assessments were used to monitor the load throughout trainings and games. In weekly external load, there were differences between the four microcycles, with a lower load in MIC5 for all the parameters and higher on MIC9 in the most of them (p < 0.05). In RPE, MIC9 (229 ± 60 arbitrary units (au)) differed significantly from MIC5 (229 ± 60 au, p < 0.001), MIC6 (281 ± 67 au; p < 0.001) and MIC7 (297 ± 48 au, p = 0.009). MIC5 also differed from MIC6 (p = 0.001) and MIC7 (p < 0.001). In the game external load, the only differences found in GDEC2 (game decelerations) were between MIC7 (68 ± 10 number (n)), MIC5 (61 ± 11 n, p = 0.035) and MIC6 (60 ± 10 n, p = 0.002); in GSPEF (game speed efforts), between MIC5 (40 ± 17 n), MIC7 (48 ± 14 n, p = 0.004) and MIC9 (48 ± 16 n, p < 0.001) and between MIC6 (41 ± 14 n), MIC7 (p = 0.009), and MIC9 (p = 0.009); in GMPW5 (game metabolic power efforts), between MIC7 (1307 ± 271 n), MIC5 (1201 ± 340 n, p = 0.035) and MIC6 (1178 ± 261 n, p = 0.001). No differences were found for wellness and perceived exertion. It is important for performance coaches to adapt the training load to the length of the microcycle, applying a lower load to short training weeks and manage the load fluctuation on long training weeks in terms of volume, intensity and recovery. In our study, the results confirmed that this strategy could result in similar performance in the games, regardless of microcycle length.