Monitoring mood state to improve performance in soccer players: A brief review

Establishing the minimal important difference of the visual analog scale for assessing exercise-induced fatigue

BACKGROUND

Exercise-induced fatigue is a physiological state characterized by performance decline. The Visual Analog Scale (VAS) is one of the most commonly used subjective methods for evaluating exercise-induced fatigue. However, there is a limited interpretation of how much a change in this method indicates a fatigue status that matters to the exercise performance due to the lack of a well-established minimal important difference (MID).

METHODS

This study is a secondary analysis of data from three trials. We analyzed individual participant data before and after exercise-induced fatigue. Anchor-based methods were used to determine the MID of the VAS for fatigue, using Countermovement Jump (CMJ) height as an anchor. Specifically, the MID was calculated using mean change, receiver operating characteristic (ROC) curve analysis, and linear regression methods.

RESULTS

Data from 71 participants (80.28% male, 22.85 ± 2.51 years), corresponding to 230 person-time measurements, were included in this analysis. The CMJ height fulfilled the requirements to be used as an anchor. MIDs for mean change, ROC curve, and linear regression analysis were 48.51, 44.13, and 43.08, respectively. The Youden's Index indicated that the MID calculated by the mean change method was the most relevant and reliable in distinguishing between fatigued and non-fatigued states.

CONCLUSIONS

This study establishes a MID (48.51) for interpreting changes in VAS scores. Future research utilizing VAS to assess exercise-induced fatigue should not only consider statistical differences but also examine whether the changes meet the MID threshold to interpret the actual impact of interventions.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR), Registration Number: ChiCTR2500095599 (Retrospectively registered; registration date: 09/01/2025).

Cross-cultural validation of the profile of mood scale: evaluation of the psychometric properties of short screening versions

The Profile of Mood States (POMS) is one of the most widely applied scales for measuring mood. Considering the advantages of short scales and increased international research, the aim of the present study was to evaluate cross-culturally the psychometric properties of a short 16-item version of the POMS. Data were collected from 15,693 participants across 10 different countries worldwide. Initially, we identified the original versions of the POMS in various languages. Subsequently, we selected 16 items based on the previously validated short form (POMS-16) for analysis. Psychometric properties of the POMS were then evaluated in samples from each studied population for each language version. Confirmatory factor analysis was conducted to assess its invariance across age groups and gender, alongside reliability estimation. Most language versions of the POMS-16 showed a good fit with the four-factor model, except for the Chinese (traditional) and Turkish versions. Reliability was generally high, except for the Vigor subscale in a small subset of languages. Regarding measurement invariance, the majority of language versions were invariant across gender and age groups, except for the Farsi language version across gender, and the Chinese, Farsi, Finnish, and Turkish versions across age. These findings enhance the cross-cultural applicability of the POMS-16, contributing to its utility in diverse populations and thus enhancing the comparability of the results. In addition, we introduced the first versions of the POMS in Farsi, Finnish, and Icelandic.

Comparisons of Types of Schematic Diagrams and Time of Day of Instruction for Teaching Soccer Tactics

Our purpose in this study was to explore how types of schematic diagrams and diurnal timing of instruction of soccer tactics affect physical education undergraduates' learning. We partly randomized student assignments to three schematic conditions: (a) diagrams with simultaneous arrows, (b) diagrams with sequential-transient arrows, or (c) diagrams with sequential-permanent arrows. Each of 45 participants attended a morning session (08h00-09h00) and an afternoon session (16h00-17h00) on two different days. Each session involved oral temperature and mood state measurements, a study phase (in which the participant studied how the play system functioned), and then a recall-reconstruction task. We found that morning sessions were associated with better recall performance than late afternoon sessions, regardless of the schematic diagram format. Moreover, students derived greater benefit from diagrams featuring both sequential-transient and sequential-permanent arrows in both morning and afternoon sessions, with a clear relative advantage for the diagrams with sequential-permanent arrows. During morning sessions, compared to afternoon sessions, participants showed lower oral temperature, lower negative mood, and higher positive mood. We discuss these findings and their implications for the acquisition of tactical information about soccer.

Molecular, Physical, and Technical Performance Response After a Competitive Match in Male Professional Soccer Players

BACKGROUND

Male professional soccer players frequently compete in multiple matches weekly, and each match significantly impacts their homeostasis, health, and performance. This study evaluates players response at 48 h post-match by combining biological and GPS data. Investigating biochemical and performance metrics offers insights into the physical demands of high-intensity exercise, essential for optimizing performance, recovery, and overall athlete health.

METHODS

The study involved an Italian "Serie A" team, and we assessed players' effort during a single match using GPS data and compared it to "Serie A" averages. Additionally, we evaluated oxidative stress and metabolism 48 h after the match.

RESULTS

At 48 h post-match, there were no signs of oxidative stress and changes in salivary IgA levels, but total antioxidant potential was significantly low. Moreover, increased plasma metabolites linked to energy production were also observed.

CONCLUSIONS

The results indicate that 48 h after a match in "Serie A", well-trained athletes showed no oxidative stress, to the detriment of the antioxidant potential, along with increased metabolites crucial for energy production. Combining GPS and metabolic analysis enhances player performance, informs tactical decisions, and supports team success, fostering data-driven approaches in soccer.

Supplementation of L-glutamine enhanced mucosal immunity and improved hormonal status of combat-sport athletes

BACKGROUND

Maintaining proper immune function and hormone status is important for athletes to avoid upper respiratory tract infection (URTI) and insufficient recovery, which is detrimental to sport performance and health. The aim of this study was to evaluate whether three-week supplementation of L-glutamine could benefit the mucosal immunity and hormonal status of combat-sport athletes as well as their rates of upper respiratory tract infection (URTI) and subjective feelings of well-being after intensive training.

METHODS

Twenty-one combat-sport athletes from the National Taiwan University of Sport were recruited in this study. After intensive training, two groups of the participants were asked to consume powder form of 0.3 g/kg body weight of L-glutamine (GLU group) or maltodextrin (PLA group) with drinking water in a randomized design at the same time every day during 3 weeks. Saliva samples were collected to measure immunoglobulin A (IgA), nitric oxide (NO), testosterone (T) and cortisol (C) before and after three-week supplementation; moreover, Hooper's index questionnaires were completed for wellness assessment. The incidence and duration of URTI were recorded by using a health checklist throughout the entire study period.

RESULTS

Supplementation of L-glutamine significantly enhanced the concentrations of IgA and NO in saliva; additionally, the incidence of URTI was significantly reduced. Regarding hormones, T concentration was significantly decreased in the PLA group, whereas C concentration was significantly increased, resulting in a significant decrease of T/C ratio. In contrast, the GLU group showed a significant increase of T/C ratio, while the mood scores of the Hooper's index questionnaire were higher in the PLA group.

CONCLUSIONS

Three-week supplementation of L-glutamine after intensive training enhanced the mucosal immunity, improved hormonal status and reduced the rate of URTI of combat-sport athletes while feelings of well-being were also enhanced. Therefore, L-glutamine would be beneficial for the sports performance and recovery of athletes.

Comparative Analysis of the Physical, Tactical, Emotional, and Mood Characteristics of Under-13 Soccer Players by Performance Level

Background and Objectives: Soccer is a sport characterized by various unpredictable situations in which physical abilities are associated with athletic performance. There are several capabilities that young soccer players must develop to adapt to the needs of the competition. This study analyzes the physical characteristics, tactical knowledge, emotional intelligence, and mood states of youth soccer players at different competitive levels. Materials and Methods: The sample consisted of 36 male soccer players with an average age of 12.65 ± 0.48 years, weight of 44.92 ± 7.49 kg, and height of 157.2 ± 0.08 cm. A cross-sectional correlational study design was selected. Inferential analysis was conducted via the RV coefficient to assess relationships between groups. Two-sample tests (Student's t test or the Mann-Whitney U test) were used to assess the distribution of the samples. Standardized mean differences (i.e., Cohen's d) were calculated as effect sizes. Results: For the yo-yo intermittent endurance test level 1, the Premier category showed higher speed (p = 0.01, d = 0.40) and superior estimated VO2max (p = 0.01, d = -0.91). The statistically significant variables included the hamstring strength exercise of the hamstrings for the angle of rupture (p = 0.04, d = -0.04, d = -0.72), the COD-Timer 5-0-5 for contact time-5-0-5 (ms) (p = 0.04, d = 0.69) and 10 m-5-0-5 (s) (p = 0.02, d = 0.79), tactical knowledge of in-game performance (p = 0.01, d = -1.19), support level (p = 0.01, d = -1.27), decision-making ability (p = 0.01, d = 0.59), melancholy (p = 0.01, d = 0.59), confusion (p = 0.01, d = 0.56), and emotional intelligence (p = 0.04, d = 0.77). The Premier category presented slightly higher averages than did category A. In the assessment of running-based anaerobic sprint test power (p < 0.05, d = 0.83) and mood states (p < 0.05, d = 0.59), players in category A presented higher results. Conclusions: The performance capacity of youth soccer players encompasses a multidimensional complexity that includes physical, tactical, emotional, and psychological aspects, which vary among players of the same age.

Optimizing performance and mood state in competitive swimmers through tapering strategies

Tapering is a concept that is of great importance in relation to performance, due of its great effect on the psychological and physical condition of the swimmer. Therefore, the present study aims to investigate the effect of two-week of tapering characterized by a progressive training volume reduction on mood state and swimming performance in competitive swimmers. Twenty-four competitive male swimmers were randomly assigned into two groups. Experimental group (age = 16.9 ± 0.5 years) and control group (16.1 ± 0.4 years). The mood subscales (tension, depression, anger, fatigue, confusion and vigor), total mood disturbance and swimming performance (50-m front crawl) were measured in pre and posttest. Our findings revealed a significant improvement in mood subscales (20.8 to 47.8%), total mood disturbance (14.4%) and in swimming performance (3.5%) after 2 weeks of tapering training. A significant correlation was observed between the total mood disturbance and the 50 m front crawl (r = -0.63) only in the experimental group. It was concluded that a progressive reduction in training volume with a maintain of intensity could improve mood state and swimming performance. In addition, a change in total mood disturbance could affect swimming performance. Swimming coaches are advised to include tapering period according to the standards we mentioned earlier before competitive swimming to improve mental state, which helps the swimmers to overcome the negative influences of overtraining and therefore they can promote sprint-swimming performance.

Effectiveness of Chinese Herbal Medicine in Postoperative Fatigue Syndrome Following Total Joint Arthroplasty or Hip Fracture Surgery: Evidence from Randomized Controlled Trials

BACKGROUND

There is no high-quality, evidence-based protocol for the treatment of postoperative fatigue syndrome (POFS) after total joint arthroplasty (TJA) or fracture surgery with Chinese herbal medicine (CHM).

PURPOSE

The purpose of this study was to explore the efficacy of CHM in the treatment of POFS after TJA or hip fracture surgery (HFS).

METHODS

We searched six databases to obtain randomized controlled trials (RCTs) of CHM for the treatment of POFS after TJA or HFS. The retrieval time limit was from the establishment of each database to August, 2022. According to the Cochrane Handbook for Systematic Reviews version 5.1, we used RevMan 5.3 to evaluate the quality of the studies. Stata 14.0 software was used to merge and analyze the data. The weighted mean difference (WMD) was the effect estimate for statistical analysis. We also performed subgroup analyses according to different types of surgeries.

RESULTS

A total of 11 RCTs were included in this study, comprising 430 cases in the CHM group and 432 cases in the control group (CG). The meta-analysis results showed that there was no significant difference in the Brief Profile of Mood States (BPOMS) score (WMD=0.08, 95% confidence interval (CI): -0.29 to 0.45, P=0.688), Christensen Fatigue scale (CHFS) score (WMD = 0.15, 95% CI: -0.09 to 0.39, P=0.214) or Identity-Consequence Fatigue Scale (ICFS) score (WMD=-0.40, 95% CI: -1.84 to 1.05, P=0.589) between the CHM group and the CG on the first postoperative day. The use of CHM significantly reduced the BPOMS score (WMD=-0.85 and WMD=-3.01, respectively), CHFS score (WMD=-1.01 and WMD= -1.45, respectively), and ICFS score (WMD=-3.51 and WMD=-5.26) on postoperative days 3 and 7. Compared with the CG, the CHM group had significantly increased serum transferrin and IgG levels on postoperative days 3 and 7. The subgroup analysis results suggested that the application of CHM in HFS patients improved fatigue symptoms on postoperative days 3 and 7, while the application of CHM to treat POFS in TJA patients had great inconsistency in the evaluation of different indicators.

CONCLUSION

The application of CHM improved the fatigue status of POFS patients after TJA or HFS and increased the levels of transferrin and IgG in serum, which is conducive to promoting the postoperative rehabilitation process of patients. The subgroup analysis results showed that the application of CHM to intervene in POFS in HFS patients had obvious benefits.