Muscle Activation in Middle-Distance Athletes with Compression Stockings

The Effects of Lower Leg Compression Garments on Lower Extremity Sports Injuries, Subjective Fatigue and Biomechanical Variables: A Systematic Review with Meta-analysis

The objective of this study was to systematically review the literature on the effect of CGs versus non-CGs (such as regular socks) or versus placebo garments on 1) the incidence of lower extremity sports injuries and 2) subjective ratings of fatigue and biomechanical variables in athletes at participating in any sport that required any level of running performance, given that fatigue-related biomechanical alterations may increase the risk of sports injuries. This study was a systematic review with meta-analyses. PubMed, Embase, CINAHL, Cochrane, PEDro, and Scopus were searched for eligible studies until 7 July 2021. Two reviewers independently assessed the risk of bias using the Cochrane Collaboration's tool for risk of bias. Meta-analyses were performed using a random-effects model. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of evidence for all outcome measures. Twenty-three studies, all with a high risk of bias, were included. Nineteen studies were used in the meta-analyses. No studies focused on the effect of CGs on the incidence of lower extremity sports injuries in athletes. Seventeen studies investigated the effect of CGs on subjective ratings of fatigue, but meta-analysis showed no difference in effectiveness between CGs versus non-CGs (such as regular socks) and versus placebo CGs (low certainty evidence). Because of heterogeneity, pooling of the results was not possible for the biomechanical variables. Nonetheless, low certainty evidence showed no effect of CGs. We identified no evidence for a beneficial or detrimental effect of lower leg CGs on the occurrence of lower extremity sports injuries, subjective ratings of fatigue, or biomechanical variables in athletes at any level of running performance. Based on the variable use of running tests, definitions used for biomechanical variables, and reporting of CG characteristics and more standardized reporting is recommended for future studies evaluating CGs.

Effects of protein-carbohydrate vs. carbohydrate alone supplementation on immune inflammation markers in endurance athletes: a randomized controlled trial

PURPOSE

The impact of ingesting carbohydrates alone or combined with proteins to support exercise immune adaptation in endurance athletes is scarcely investigated. The present study compares the effect of ingesting a combined protein-carbohydrate supplement vs. a carbohydrate-only supplement post-workout on immune inflammation markers following a 10 week periodized endurance training program in well-trained athletes.

METHODS

Twenty-five men completed the study after being randomly assigned to one of the following intervention groups: combined protein-carbohydrate (PRO-CHO n = 12, 31 ± 9 years, [Formula: see text]O_2peak 61.0 ± 5.6 ml^.kg^-1.min^-1) or non-protein isoenergetic carbohydrate (CHO, n = 13, 33 ± 8 years, [Formula: see text]O_2peak 60.6 ± 6.9 ml^.kg^-1.min^-1). Treatment consisted of ingesting 24 g of assigned supplement, mixed with 250 ml of orange juice, once a day for 10 weeks immediately post-workout (or before breakfast on non-training days). Measurements were conducted pre- and post-intervention on total leukocytes, leukocyte subsets (i.e., neutrophils, eosinophils, basophils, monocytes, and lymphocytes), and platelets. The inflammatory status was assessed by the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), and the systemic-immune inflammation index (SII).

RESULTS

Post-intervention, significant increases were observed for CHO group only for the three inflammatory markers: NLR (p = 0.050, d = 0.58), PLR (p = 0.041, d = 0.60), and SII (p = 0.004, d = 0.81) but not for PRO-CHO (p > 0.05).

CONCLUSION

Ingesting a post-workout protein-carbohydrate combined beverage promoted a more favourable immune status than carbohydrate-only ingestion by attenuating cellular inflammation over a 10 week training period in endurance male athletes.

TRIAL REGISTRATION

The study was registered in ClinicalTrials.gov with the following ID: NCT02954367. The study was registered by 3 November 2016.

Putting the Squeeze on Compression Garments: Current Evidence and Recommendations for Future Research: A Systematic Scoping Review

Background

Compression garments are regularly worn during exercise to improve physical performance, mitigate fatigue responses, and enhance recovery. However, evidence for their efficacy is varied and the methodological approaches and outcome measures used within the scientific literature are diverse.

Objectives

The aim of this scoping review is to provide a comprehensive overview of the effects of compression garments on commonly assessed outcome measures in response to exercise, including: performance, biomechanical, neuromuscular, cardiovascular, cardiorespiratory, muscle damage, thermoregulatory, and perceptual responses.

Methods

A systematic search of electronic databases (PubMed, SPORTDiscus, Web of Science and CINAHL Complete) was performed from the earliest record to 27 December, 2020.

Results

In total, 183 studies were identified for qualitative analysis with the following breakdown: performance and muscle function outcomes: 115 studies (63%), biomechanical and neuromuscular: 59 (32%), blood and saliva markers: 85 (46%), cardiovascular: 76 (42%), cardiorespiratory: 39 (21%), thermoregulatory: 19 (10%) and perceptual: 98 (54%). Approximately 85% (n = 156) of studies were published between 2010 and 2020.

Conclusions

Evidence is equivocal as to whether garments improve physical performance, with little evidence supporting improvements in kinetic or kinematic outcomes. Compression likely reduces muscle oscillatory properties and has a positive effect on sensorimotor systems. Findings suggest potential increases in arterial blood flow; however, it is unlikely that compression garments meaningfully change metabolic responses, blood pressure, heart rate, and cardiorespiratory measures. Compression garments increase localised skin temperature and may reduce perceptions of muscle soreness and pain following exercise; however, rating of perceived exertion during exercise is likely unchanged. It is unlikely that compression garments negatively influence exercise-related outcomes. Future research should assess wearer belief in compression garments, report pressure ranges at multiple sites as well as garment material, and finally examine individual responses and varying compression coverage areas.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01604-9.

Sensitivity of the properties of the graduated compression stocking and soft tissues on the lower limb-stocking interfacial pressure using the orthogonal simulation test

Graduated compression stocking (GCS) plays an important role in the treatment of venous disease in the lower limb. However, the effect of the variation in the mechanical properties of the GCS and the soft tissues on the treatment of the venous disease in the lower limb remains unclear. The aim of the present study was to investigate the influence of the material properties of the GCS and soft tissues on the lower limb-stocking interfacial pressure using the orthogonal simulation test. A three-dimensional finite element (FE) model of the lower limb was established using the MRI dataset of a 40-year-old volunteer. The bones, the skin, the veins and the skeletal muscles were reconstructed in the FE model. The FE model of the GCS was generated using the information provided by the manufacturer. Then the parameter sensitivity analysis was performed using a two-step orthogonal simulation test. The first-step orthogonal test showed that the variation in the Young's modulus in the wale direction of the GCS induced a change of 0.37 mmHg in the lower limb-stocking interfacial pressure in the ankle section. The second-step orthogonal test showed that the variations in the Young's modulus in the wale direction of the GCS in the knee section induced the changes of 0.05 mmHg, 0.15 mmHg and 0.60 mmHg in the interfacial pressure in the ankle, the calf and the knee, respectively. In conclusion, the Young's modulus in the wale direction of the GCS and the Poisson's ratio of the GCS are the parameters significantly influencing the lower limb-stocking interfacial pressure. The interfacial pressure in the ankle is not sensitive to the Young's modulus in the wale direction of the GCS in the knee section. However, the interfacial pressures in the calf and knee are sensitive to the Young's modulus in the wale direction of the GCS in the knee section. These data provide important information for the design of GCS.