Review of exercise-induced physiological control models to explain the development of fatigue to improve sports performance and future trend

The effect of high-intensity intermittent and moderate-intensity continuous exercises on neurobiological markers and cognitive performance

BACKGROUND

The effects of exercise on cognitive functions and general brain health have been increasingly studied. Such studies conducted among athletes are very important to understanding the effects of different exercise methods on biochemical parameters and cognitive performance. The present study aimed to compare the neuroprotective effects of high-intensity interval exercise (HIIE) and moderate-intensity continuous exercise (MICE) based on biochemical parameters and cognitive performance in athletes.

METHODS

A total of twenty-eight elite male boxing athletes aged > 18 years, with at least eight years of training experience, who successfully achieved national and international levels were included in this study. The elite athletes participating in the study were aged 24.43 ± 4.72 years, 14.45 ± 5.89 years of training experience, had a body weight of 74.64 ± 7.82 kg, and had a height of 177 ± 7.15 cm. Athletes who consumed any stimulants during the testing or supplementation phase, nutritional supplements, or steroids that may have affected hormone levels or sports performance in the last three months were excluded from this study. Venous blood samples were obtained, and cognitive performance tests (Stroop tests) were applied (i) immediately after high-intensity intermittent exercise (HIIE), (ii) one hour after HIIE, (iii) immediately after moderate-intensity continuous exercise (MICE), and (iv) one hour after MICE. Serum BDNF, S100B, and NSE levels were measured after each session.

RESULTS

Serum BDNF levels were significantly (F = 2.142, P < 0.001, ηp 2 = 0.589) greater in the HIIE group (5.65 ± 1.79 ng/mL) than in the control group (1.24 ± 0.54 ng/mL) and MICE group (3.38 ± 1.29 ng/mL) for the samples obtained immediately after exercise. Serum S100B levels were significantly (F = 3.427, P < 0.001, ηp 2 = 0.427) greater in the HIIE group (71.92 ± 23.05 ng/L) than in the control group (47.39 ± 15.78 ng/L), however there was no significant difference between the HIIE and MICE groups (59.62 ± 28.90 ng/L) in the samples obtained immediately after exercise. Serum NSE levels were significantly (F = 1.475, P < 0.001, ηp 2 = 0.312) greater in the HIIE group (14.57 ± 2.52 ng/mL) than in the control group (9.51 ± 3.44 ng/ML mL), however there was no significant difference between the HIIE and MICE groups (59.62 ± 28.90 ng/L) in the samples obtained immediately after exercise. Compared with control groups, both HIIE and MICE improved cognitive performance demonstrated by the Stroop test results. Again, HIIE was superior to MICE in terms of Stroop task reaction time and error rate (incongruent task) scores.

CONCLUSION

HIIE and MICE have favorable effects on improving cognitive performance and neuroprotection in an athlete population. HIIE is considered to be superior to MICE in improving neuroprotection and cognitive performance. Our study has remarkable results demonstrating the benefits of HIIT on neuroprotection and cognitive performance. HIIE is recommended instead of MICE, especially in sports where cognitive performance is more important.

Polysaccharides derived from natural edible and medicinal sources as agents targeting exercise-induced fatigue: A review

Exercise-induced fatigue (EF) is a common occurrence during prolonged endurance and excessive exercise and is mainly caused by energy depletion, harmful metabolite accumulation, oxidative stress, and inflammation. EF usually leads to a reduction in initiating or maintaining spontaneous activities and muscle performance and ultimately results in a decrease in the quality of life of people who engage in physical work. Therefore, the interest in investigating EF-targeting agents with minimal side effects and good long-term efficacy has substantially increased. Natural edible and medicinal polysaccharides have shown positive anti-EF effects, but the relevant reviews are rare. This review comprehensively summarizes studies on natural polysaccharides from edible and medicinal sources that can relieve EF and improve physical performance from the past decade, focusing on their sources, monosaccharide compositions, anti-EF effects, and possible molecular mechanisms. Most of these anti-EF polysaccharides are heteropolysaccharides and are mainly composed of glucose, arabinose, galactose, rhamnose, xylose, and mannose. In EF animal models, the polysaccharides exert positive EF-alleviating effects through energy supply, metabolic regulation, antioxidation, anti-inflammation, and gut microbiota remodeling. However, further studies are still needed to clarify the anti-EF effects of these polysaccharides on human beings. In summary, the present review expects to provide scientific data for the future research and development of natural polysaccharide-based anti-EF drugs, dietary supplements, and health-care products for specific fatigue groups.

Panax ginseng improves physical recovery and energy utilization on chronic fatigue in rats through the PI3K/AKT/mTOR signalling pathway

CONTEXT

Panax ginseng C. A. Meyer (Araliaceae) is a tonic herb used in ancient Asia.

OBJECTIVE

This study investigated the antifatigue effect of P. ginseng on chronic fatigue rats.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into control, model and EEP (ethanol extraction of P. ginseng roots) (50, 100 and 200 mg/kg) groups (n = 8). The rats were subcutaneously handled with loaded swimming once daily for 26 days, except for the control group. The animals were intragastrically treated with EEP from the 15th day. On day 30, serum, liver and muscles were collected, and the PI3K/Akt/mTOR signalling pathway was evaluated.

RESULTS

The swimming times to exhaust of the rats with EEP were significantly longer than that without it. EEP spared the amount of muscle glycogen, hepatic glycogen and blood sugar under the chronic state. In addition, EEP significantly (p < 0.05) decreased serum triglycerides (1.24 ± 0.17, 1.29 ± 0.04 and 1.20 ± 0.21 vs. 1.58 ± 0.13 mmol/L) and total cholesterol (1.64 ± 0.36, 1.70 ± 0.15 and 1.41 ± 0.19 vs. 2.22 ± 0.19 mmol/L) compared to the model group. Regarding the regulation of energy, EEP had a positive impact on promoting ATPase activities and relative protein expression of the PI3K/Akt/mTOR pathway.

CONCLUSIONS

Our results suggested that EEP effectively relieved chronic fatigue, providing evidence that P. ginseng could be a potential dietary supplement to accelerate recovery from fatigue.

Evaluation of the Training Session in Elite Paralympic Powerlifting Athletes Based on Biomechanical and Thermal Indicators

BACKGROUND

Paralympic powerlifting (PP) is performed on a bench press, aiming to lift as much weight as possible in a single repetition.

PURPOSE

To evaluate thermal asymmetry and dynamic force parameters with 45 and 80% 1 Repetition Maximum (1 RM) in PP athletes.

METHODS

Twelve elite PP male athletes were evaluated before and after a training session regarding skin temperature (thermography) and dynamic force indicators (Average Propulsive Velocity-MPV, Maximum Velocity-VMax, and Power). The training consisted of five series of five repetitions (5 × 5) with 80% 1 RM. The force indicators and dynamics before and after (45% 1 RM) were evaluated in series "1" and "5" with 80% 1 RM.

RESULTS

The temperature did not present asymmetry, and there were differences between the moment before and after. In MPV, Vmax, and Power, with 45% 1 RM, there were differences both in asymmetry and in moments (p < 0.005). With 80% 1 RM, asymmetry was observed, but no differences between moments (p < 0.005).

CONCLUSION

No thermal asymmetry was observed. There were reductions in MVP and VMax at 45 and 80% 1 RM but without significant differences between time points (before and after). However, there was asymmetry in the moments before and after within a safety standard, where Paralympic powerlifting was safe in terms of asymmetries.

Relationship between Repeated Sprint Ability, Countermovement Jump and Thermography in Elite Football Players

Football is a very demanding sport which requires players to exert maximum effort, producing fatigue and eventually injuries. Thermography can be used to detect fatigue and prevent its consequences through thermal asymmetries in the bilateral body areas; however, its adequacy for elite footballers has not been widely studied. Therefore, the objective of the present investigation was to determine the suitability of thermography to detect fatigue in male football players. For this reason, twenty participants were gathered into a pair of subgroups (low [<0.2 °C] vs. high thermal asymmetry [≥0.2 °C]) based on a thermography session of the lower limbs (thighs, calves, and hamstrings). After the thermography session, players performed CMJs before and after an RSA test (6 × 30 m/20″). A mixed two-way analysis of variance and Bonferroni post hoc pairwise comparisons were undertaken to analyse the results. No significant differences (p > 0.05) were found in any of the RSA test variables between low and high thermal asymmetry groups for thighs and calves. On the other hand, the low thermal asymmetry hamstring group reported a smaller percentage difference in sprints for the first sprint (%Diff) and a larger percentage difference in sprints two and three with respect to the best sprint (%Best). For CMJs, the low thermal asymmetry hamstring group reported significantly higher values post-RSA test, indicating better performance. Accordingly, thermography can provide information about performance in CMJ and RSA tests through hamstring asymmetries over 0.2 °C. Meanwhile, larger asymmetries than 0.2 °C in calves and thighs do not seem to be related to performance in these tests; therefore, coaches should consider if it is optimal to align players with high hamstring asymmetries.

DIAGNOSIS OF SPORTS FATIGUE AND NUTRITIONAL INTERVENTION IN TRACK AND FIELD

ABSTRACT Introduction As a high-intensity physical sport, athletics can easily cause serious physical injuries and even psychological problems if not diagnosed after sports fatigue. Objective Study the relationship between sports fatigue and nutritional intervention in track and field. Methods One hundred track and field athletes in a province were investigated. Through literature survey, questionnaire survey, and other data testing, track and field athletes’ sports fatigue and nutritional status were analyzed to determine the necessary relationship between sports fatigue and nutritional intervention. Results The coach’s judgment of sports fatigue during athletes’ training is characterized by a lack of technical accuracy, leading to the decline of athletes’ physical recovery ability and aggravating sports fatigue to a certain extent. As a high-intensity physical exercise, athletics must diagnose sports fatigue in time and provide effective nutritional intervention. Conclusion The research shows that after high-intensity exercise, the diagnosis of sports fatigue in track and field athletes is of great importance in judging the athletes’ physical function, and scientific nutritional intervention plays an important role in athletes’ excessive physical function, improving their sports ability and relieving sports fatigue. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

EXERCISE FATIGUE INJURY UNDER SPORT RESISTANCE

ABSTRACT Introduction Athletes are prone to local muscle fatigue due to high-intensity training and to long-term accumulation of musculoskeletal injuries. Musculoskeletal complications represent a large proportion of occupational health problems and, for this reason, have received increased attention from the sports industry. In this sense, studies on muscle fatigue should be intensified. Objective Verify muscle fatigue and injury involving the strain characteristics of lower limb joints in the eccentric and centripetal contraction of the jump. Methods A total of 691 individuals aged 20 to 40 years were selected. Fatigue was caused by active muscle contraction. The characteristic curves of active muscle contraction in different isometric, isotonic, and isokinetic training were analyzed. The degree of fatigue caused by three different sports states was tested by experimentation. The corresponding active muscle contraction characteristics were also analyzed. The potential for homeostasis at different ages was compared. Results The delay in recovery to fatigue is directly proportional to the athlete’s age. The return to post-exercise relief proportion from fatigue gradually decreases. Conclusion The experimental results showed that active muscle contraction could reduce exercise fatigue to some extent. This beneficial biochemical property of active muscle contraction is not found in people with advanced age. The findings have a guiding potential for the relief of sports fatigue. Evidence Level II; Therapeutic Studies - Investigating the result.

Development of Basketball Tactics Basic Cooperation Teaching System Based on CNN and BP Neural Network

The traditional basketball teaching mode cannot meet the needs of students for the basic cooperation of basketball tactics. Therefore, a basic cooperation teaching system of basketball tactics based on artificial neural network is studied and designed. The system has a professional basketball game video tactical learning module. The events in the basketball game video are classified through a convolutional neural network and combined with the explanation of teachers to make the students have an intuitive understanding of the basic cooperation of basketball tactics and then design the basketball game module based on a BP neural network to provide students with an online basketball tactics training platform. Finally, the teacher scores the performance of the actual on-site training students in the basic cooperation of basketball tactics through the tactical scoring module on the system. The results show that after the introduction of global and collective motion patterns, the classification accuracy of the convolutional neural network is improved by 22.48%, which has significant optimization. The average accuracy of basketball game video event classification is 62.35%, and the accuracy of snatch event classification is improved to 95.28%. The recognition rate of the BP neural network combined with momentum gradient descent method is 75%, the number of weight adjustment is less, and the memory is small while ensuring fast running speed. Students who accept the basic basketball tactics cooperation teaching system based on the artificial neural network for basketball teaching have an overall score of 27.99 ± 2.11 points The overall score of exchange defense cooperation was 24.12 ± 2.03, which was higher than that of the control group. The above results show that the basketball tactical basic cooperation teaching system based on the artificial neural network has a good teaching effect in improving students' basketball tactical basic cooperation ability.

The Knowledge Map of Sport and Exercise Psychology: An Integrative Perspective

The present work contains a personal perspective on what sport and exercise psychology (SEP) is today. It is a global synthesis of research about psychological aspects related to the context and practice of sport and exercise. The intended impact was to positively influence teaching SEP to students, to promote interdisciplinary research and practice, and to assist the development of SEP as an applied science by helping experts develop a more holistic view of the field. Over 650 theoretical and review articles about psychological concepts in connection to sport and exercise were read in the process of creating a conceptual model that reflects the essence of SEP and leads to a conceptualization of SEP based on research topics. The result was a knowledge map of SEP made up of four main research clusters: biopsychological descriptors, external variables, psychological skills, and applied SEP practice. In terms of interdisciplinarity, the present perspective on SEP suggests that sport and exercise can be used as a research paradigm or natural laboratory to study psychological aspects relevant to various scientific fields, and that sport and exercise can be used as a therapeutic framework in response to challenges that researchers and practitioners in these fields are typically addressing.