Wearing Compression Garment after Endurance Exercise Promotes Recovery of Exercise Performance

Effects of Photobiomodulation and Low-Intensity Stretching on Delayed-Onset Muscle Soreness: A Randomized Control Trial

Objective: This study aimed to investigate the effects of photobiomodulation (PBM), low-intensity stretching, and their combination on delayed-onset muscle soreness (DOMS) in the untrained population. The relationships between DOMS and muscle function and functional performance were also tested. Methods: Fifty-four participants were randomized into four groups. Eccentric exercise was used to induce DOMS. Each group received either no treatment, PBM, stretching or PBM combined with stretching at 24, 48, and 72 h postexercise. Pressure pain threshold (PPT), numerical rating scale (NRS), single-leg forward jump (SLFJ), and maximum isometric voluntary contraction (MIVC) were measured at baseline, 24, 48, 72, and 96 h after eccentric exercise. Between-group differences were tested using two-way repeated measures analysis of variance and the relationships between DOMS and MIVC, and SLFJ were examined using Pearson's correlation analysis. Results: The PPT at the vastus medialis and vastus lateral in the PBM combined with stretching group was significantly lower than that in control group at 72 h (p = 0.045) and 48 h (p = 0.037) postexercise. No significant between-group difference in PPT was found for the rest occasions. There was no significant between-group difference in NRS, MVIC, and SLFJ on any occasion (p ≥ 0.052). DOMS was not correlated with MIVC and SLFJ (p ≥ 0.09). Conclusions: PBM or low-intensity stretching did not affect DOMS and functional performance in untrained individuals. The combination of PBM and low-intensity stretching increased pain sensitivity and did not relieve soreness. The DOMS was not associated with either muscle function or functional performance.

Compression-induced improvements in post-exercise recovery are associated with enhanced blood flow, and are not due to the placebo effect

The aim of this study was to investigate the physiological effects of compression tights on blood flow following exercise and to assess if the placebo effect is responsible for any acute performance or psychological benefits. Twenty-two resistance-trained participants completed a lower-body resistance exercise session followed by a 4 h recovery period. Participants were assigned a post-exercise recovery intervention of either compression tights applied for 4 h (COMP), placebo tablet consumed every hour for 4 h (PLA) or control (CON). Physiological (markers of venous return, muscle blood flow, blood metabolites, thigh girth), performance (countermovement jump, isometric mid-thigh pull), and psychological measures (perceived muscle soreness, total quality of recovery) were collected pre-exercise, immediately post-exercise, at 30 (markers of venous return and muscle blood flow) and 60 min (blood metabolites, thigh girth and psychological measures) intervals during 4 h of recovery, and at 4 h, 24 h and 48 h post-exercise. No significant (P > 0.05) differences were observed between interventions. However, effect size analysis revealed COMP enhanced markers of venous return, muscle blood flow, recovery of performance measures, psychological measures and reduced thigh girth compared to PLA and CON. There were no group differences in blood metabolites. These findings suggest compression tights worn after resistance exercise enhance blood flow and indices of exercise recovery, and that these benefits were not due to a placebo effect.

Efficacy and Safety of TurmXTRA® 60N in Delayed Onset Muscle Soreness in Healthy, Recreationally Active Subjects: A Randomized, Double-Blind, Placebo-Controlled Trial

Background

Delayed onset of muscle soreness (DOMS) and its physiological consequences influenced an individual's adherence to an exercise routine.

Objective

This study aimed to evaluate the efficacy, safety, and tolerability of TurmXTRA® 60N (WDTE60N) on DOMS compared to placebo in recreationally active healthy subjects.

Methods

This randomized, double-blind, placebo-controlled parallel-group study enrolled 30 healthy and recreationally active subjects (average age: 28.23 ± 4.20 years) and randomized them to receive WDTE60N (WDTE60N group; n = 15) or placebo (placebo group; n = 15). Study treatments were initiated 29 days before the eccentric exercise and were continued for 4 days after the exercise. The primary endpoint was the change in pain intensity measured by the visual analog scale (VAS) at the end of study treatment (at 96 hours after eccentric exercise) from baseline (measured immediately after exercise).

Results

The VAS score indicated that subjects from the WDTE60N group reported significantly less pain after eccentric exercise compared to the placebo group (AUC_0–96h: 286.8 ± 46.7 vs. 460 ± 40.5, respectively; p < 0.0001). Well-being status was assessed using the adapted version of the Hooper and MacKinnon questionnaire and was calculated as individual and cumulative scores of the domains (fatigue, mood, general muscle soreness, sleep quality, and stress) that demonstrated improvement in all domains and in overall well-being in the WDTE60N group compared to the placebo group (p < 0.0001). Serum lactate dehydrogenase (LDH) was significantly lower in the WDTE60N group compared to the placebo group (AUC_0–96h: 23623.7 ± 2532.0 vs. 26138.6 ± 3669.5, respectively; p=0.0446).

Conclusion

Intake of WDTE60N before and after eccentric exercise significantly reduced subjective perception of muscle soreness and serum LDH activity and increased the psychological well-being in recreationally active subjects.

Acute Effects of Percussive Therapy on the Posterior Shoulder Muscles Differ Based on the Athlete's Soreness Response

Background

Percussive therapy is hypothesized to speed recovery by delivering gentle, rhythmic pulses to soft tissue. However, patients often present with a differential soreness response after percussive therapy, which may lead to altered clinical outcomes.

Purpose

To compare the acute effects of percussion therapy on passive range of motion (ROM) and tissue-specific ultrasound measures (pennation angle [PA] and muscle thickness [MT]) between healthy individuals responding positively vs. negatively to percussive therapy performed on the dominant arm posterior rotator cuff.

Study Design

Cross-sectional laboratory study.

Methods

Fifty-five healthy individuals were assessed on a subjective soreness scale before and after a five-minute percussive therapy session on the dominant arm posterior rotator cuff muscles. Participants with no change or a decrease in muscle soreness were assigned to the positive response group and participants who reported an increase in muscle soreness were assigned to the negative response group. Passive internal rotation (IR) and external rotation (ER) ROM and strength, and muscle architecture of the infraspinatus and teres minor were measured via ultrasound on the dominant shoulder. All dependent variables were collected before percussive therapy, and 20 minutes following percussive therapy.

Results

The positive response group had greater improvements than the negative response group in dominant arm IR ROM (2.3° positive vs. -1.3° negative, p=0.021) and IR strength (1.1 lbs vs. -1.2 lbs, p=0.011) after percussive therapy. No differences in ER strength or ROM were observed between groups. Regarding muscle architecture, the positive group had a lesser change in teres minor MT (0.00 mm vs. 0.11 mm, p=0.019) after percussive therapy. All other muscle architecture changes were not statistically different between groups.

Conclusion

Participants with a positive response to percussive therapy had increased dominant arm IR ROM and IR strength, and decreased teres minor MT, after percussive therapy compared to the negative response participants.

Level of Evidence

III.

In-Season Nutrition Strategies and Recovery Modalities to Enhance Recovery for Basketball Players: A Narrative Review

Basketball players face multiple challenges to in-season recovery. The purpose of this article is to review the literature on recovery modalities and nutritional strategies for basketball players and practical applications that can be incorporated throughout the season at various levels of competition. Sleep, protein, carbohydrate, and fluids should be the foundational components emphasized throughout the season for home and away games to promote recovery. Travel, whether by air or bus, poses nutritional and sleep challenges, therefore teams should be strategic about packing snacks and fluid options while on the road. Practitioners should also plan for meals at hotels and during air travel for their players. Basketball players should aim for a minimum of 8 h of sleep per night and be encouraged to get extra sleep during congested schedules since back-to back games, high workloads, and travel may negatively influence night-time sleep. Regular sleep monitoring, education, and feedback may aid in optimizing sleep in basketball players. In addition, incorporating consistent training times may be beneficial to reduce bed and wake time variability. Hydrotherapy, compression garments, and massage may also provide an effective recovery modality to incorporate post-competition. Future research, however, is warranted to understand the influence these modalities have on enhancing recovery in basketball players. Overall, a strategic well-rounded approach, encompassing both nutrition and recovery modality strategies, should be carefully considered and implemented with teams to support basketball players' recovery for training and competition throughout the season.

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.

Impact of Three Consecutive Days of Endurance Training Under Hypoxia on Muscle Damage and Inflammatory Responses

Purpose: The purpose of this study was to determine the effect of 3 consecutive days of endurance training under hypoxia on muscle damage, inflammation, and performance responses.

Methods: Nine active healthy males completed two trials in different periods, consisting of either 3 consecutive days of endurance training under hypoxia [fraction of inspired oxygen (Fio₂): 14.5%, HYP] or normoxia (Fio₂: 20.9%, NOR). They performed daily 90-min sessions of endurance training consisting of high-intensity endurance interval pedaling [10 × 4-min pedaling at 80% of maximal oxygen uptake (V˙o2max) with 2 min of active rest at 30% of V˙o2max] followed by 30-min continuous pedaling at 60% of V˙o2max during 3 consecutive days (days 1–3). Venous blood sample, muscular performance of lower limb, and score of subjective feelings were determined every morning (days 1–4) to evaluate muscle damage and inflammation. On day 4, subjects performed an incremental exercise test (IET) to evaluate the performance response.

Results: Pedaling workload during daily endurance training was significantly lower in the HYP trial (interval exercise: 166 ± 4 W) than in the NOR trial (194 ± 8 W; P < 0.0001). Serum creatine kinase (CK) and high-sensitivity C-reactive protein (hsCRP) concentrations did not significantly change during days 1–4 in either trial. Maximal voluntary contraction (MVC) of knee extension (P < 0.0001) and drop jump (DJ) index (P = 0.004) were significantly decreased with training in both trials, with no significant difference between trials. The muscle soreness and fatigue scores significantly increased in both trials (P < 0.0001). However, the HYP trial showed a significantly lower score of fatigue on day 4 compared with the NOR trial (P = 0.004). Maximal aerobic power output during IET on day 4 did not significantly differ between trials.

Conclusion: Three consecutive days of endurance training under hypoxia induced comparable levels of muscle damage, inflammation, and performance responses compared with the same training under normoxia.

Multi-Parametric Analysis of Below-Knee Compression Garments on Delayed-Onset Muscle Soreness

To investigate below-knee compression garments during exercise and a post-exercise period of 6 h on clinical, functional, and morphological outcomes in delayed-onset muscle soreness (DOMS). Eighteen volunteers (age: 24.1 ± 3.6, BMI 22.7 ± 2.7 kg/m²) were enrolled. Measures were acquired at baseline, 6 h, and 48 h after eccentric and plyometric exercise, with wearing a compression garment (21-22 mmHg) on a calf during and for the first 6 h after exercise. 3T MRI was performed for quantification of intramuscular edema (T2 signal intensity (SI), T2 time, and manual volume segmentation); jump height, calf circumference, ankle dorsiflexion (DF), creatine kinase (CK), and muscle soreness were assessed. DOMS was confirmed in all participants after 48 h, with an increase in soreness (p < 0.001) and CK (p = 0.001), decrease in jump height (p < 0.01), and the presence of intramuscular edema (p < 0.01) in both the compressed and non-compressed limbs. No differences between the compressed and non-compressed limbs were observed for muscle soreness and jump height. MRI T2 SI, T2 time, soreness, and manual segmentation revealed no effect of the compression treatment. The assessment of calf circumference and DF showed no changes in either the compression or non-compression limb (p = 1.0). Wearing compression garments during combined eccentric and plyometric exercise and for 6 h post-exercise has no effect on clinical signs of DOMS, jump performance, or the development of intramuscular edema.

Downhill Running: What Are The Effects and How Can We Adapt? A Narrative Review

Downhill running (DR) is a whole-body exercise model that is used to investigate the physiological consequences of eccentric muscle actions and/or exercise-induced muscle damage (EIMD). In a sporting context, DR sections can be part of running disciplines (off-road and road running) and can accentuate EIMD, leading to a reduction in performance. The purpose of this narrative review is to: (1) better inform on the acute and delayed physiological effects of DR; (2) identify and discuss, using a comprehensive approach, the DR characteristics that affect the physiological responses to DR and their potential interactions; (3) provide the current state of evidence on preventive and in-situ strategies to better adapt to DR. Key findings of this review show that DR may have an impact on exercise performance by altering muscle structure and function due to EIMD. In the majority of studies, EIMD are assessed through isometric maximal voluntary contraction, blood creatine kinase and delayed onset muscle soreness, with DR characteristics (slope, exercise duration, and running speed) acting as the main influencing factors. In previous studies, the median (25th percentile, Q1; 75th percentile, Q3) slope, exercise duration, and running speed were - 12% (- 15%; - 10%), 40 min (30 min; 45 min) and 11.3 km h-1 (9.8 km h-1; 12.9 km h-1), respectively. Regardless of DR characteristics, people the least accustomed to DR generally experienced the most EIMD. There is growing evidence to suggest that preventive strategies that consist of prior exposure to DR are the most effective to better tolerate DR. The effectiveness of in-situ strategies such as lower limb compression garments and specific footwear remains to be confirmed. Our review finally highlights important discrepancies between studies in the assessment of EIMD, DR protocols and populations, which prevent drawing firm conclusions on factors that most influence the response to DR, and adaptive strategies to DR.

Wearing Compression Garment Enhances Central Hemodynamics? A Systematic Review and Meta-Analysis

Lee, DCW, Ali, A, Sheridan, S, Chan, DKC, and Wong, SHS. Wearing compression garment enhances central hemodynamics? a systematic review and meta-analysis . J Strength Cond Res XX(X): 000-000, 2020-Compression garments (CG) are believed to enhance exercise performance and recovery by improving central hemodynamic responses. However, evidence is inconclusive. We performed a systematic review and meta-analysis to determine the effect of wearing CG at rest or after a physiological challenge on central hemodynamic responses, including cardiac output, stroke volume (SV), heart rate (HR), systolic blood pressure, diastolic blood pressure (DBP), and systemic vascular resistance in healthy individuals. The English language searches of the electronic databases SPORTDiscus, MEDLINE, and Web of Science were conducted from November 2018-February 2019. The studies involved were limited to the following: (a) original articles; (b) randomized controlled trials; (c) monitoring of central hemodynamic responses (either at rest or after a physiological challenge: maximal exercise or orthostatic challenge); and (d) healthy individuals. Of the 786 studies identified, 12 were included in the systematic review and meta-analysis. Meta-analysis was performed by the restricted maximum likelihood method. The results indicated that the effect size (ES) of wearing CG on improving central hemodynamic responses was large overall (Hedges' g = 0.55) and was large in SV (Hedges' g = 1.09) and HR (Hedges' g = 0.65). Subgroup analysis showed that the ESs in "post-physiological challenge" was large in overall (Hedges' g = 0.98), SV (Hedges' g = 1.78), HR (Hedges' g = 1.10), and DBP (Hedges' g = 0.75). Their ESs in "at rest" were not significant in all central hemodynamic responses, apart from a significant medium ES observed in SV (Hedges' g = 0.44). Healthy individuals who wear CG have marked improvement in central hemodynamic responses, particularly after a physiological challenge. More pronounced effects of CG are observed in increasing SV and reducing HR.

Enhanced Cycling Time-Trial Performance During Multiday Exercise With Higher-Pressure Compression Garment Wear

PURPOSE

Compression garments are widely used as a tool to accelerate recovery from intense exercise and have also gained traction as a performance aid, particularly during periods of limited recovery. This study tested the hypothesis that increased pressure levels applied via high-pressure compression garments would enhance "multiday" exercise performance.

METHODS

A single-blind crossover design, incorporating 3 experimental conditions-loose-fitting gym attire (CON), low-compression (LC), and high-compression (HC) garments-was adopted. A total of 10 trained male cyclists reported to the laboratory on 6 occasions, collated into 3 blocks of 2 consecutive visits. Each "block" consisted of 3 parts, an initial high-intensity protocol, a 24-hour period of controlled rest while wearing the applied condition/garment (CON, LC, and HC), and a subsequent 8-km cycling time trial, while wearing the respective garment. Subjective discomfort questionnaires and blood pressure were assessed prior to each exercise bout. Power output, oxygen consumption, and heart rate were continuously measured throughout exercise, with plasma lactate, creatine kinase, and myoglobin concentrations assessed at baseline and the end of exercise, as well as 30 and 60 minutes postexercise.

RESULTS

Time-trial performance was significantly improved during HC compared with both CON and LC (HC = 277 [83], CON = 266 [89], and LC = 265 [77] W; P < .05). In addition, plasma lactate was significantly lower at 30 and 60 minutes postexercise on day 1 in HC compared with CON. No significant differences were observed for oxygen consumption, heart rate, creatine kinase, or subjective markers of discomfort.

CONCLUSION

The pressure levels exerted via lower-limb compression garments influence their effectiveness for cycling performance, particularly in the face of limited recovery.

Eccentric contraction-induced muscle damage in human flexor pollicis brevis is accompanied by impairment of motor nerve

BACKGROUND

Eccentric contractions (ECCs) cause muscle damage. In addition, we showed that ECCs induce nerve dysfunction and damage with rats and human.

PURPOSE

We aimed to evaluate motor nerve conduction velocity (MCV) for flexor pollicis brevis muscle (FPBM) after ECCs.

METHODS

Twelve men (years, 19.8 ± 1.7 years; height, 172.4 ± 7.0 cm; weight, 64.0 ± 8.6 kg) performed maximal 100 ECCs on their FPBM of non-dominant hands with torque dynamometer. The dominant hands were control (CON). Maximal voluntary contraction (MVC), range of motion (ROM), DOMS, and MCV were assessed before, immediately post, and 1, 2, and 5 days after ECCs. MCV was calculated as the distance by stimulation divided by the latencies of the waveforms generated. Values were statistically analyzed by two-way ANOVA, and the significance level was set at P < .05.

RESULTS

Decreases in MVC immediately (-32.9%) to 5 days after ECCs were significantly greater (P < .05) than for the CON group. ROM showed a significant decrease immediately (-21.6%) after ECCs compared with before ECCs and CON group (P < .05). DOMS after ECCs increased at 1 and 2 days (5.0 cm) after ECCs compared with before ECCs and CON (P < .05). Also, MCV after ECCs delayed significantly from immediately (-36.4%), 1, 2, and 5 days after ECCs compared with CON (P < .05), while no significant change in M-wave amplitude was observed over time for both ECCs and CON.

CONCLUSION

The present study showed that ECCs of the FPBM cause a significant delay in MCV of median nerve.

Accelerating Recovery from Exercise-Induced Muscle Injuries in Triathletes: Considerations for Olympic Distance Races

The triathlon is one of the fastest developing sports in the world due to expanding participation and media attention. The fundamental change in Olympic triathlon races from a single to a multistart event is highly demanding in terms of recovery from and prevention of exercise-induced muscle injures. In elite and competitive sports, ultrastructural muscle injuries, including delayed onset muscle soreness (DOMS), are responsible for impaired muscle performance capacities. Prevention and treatment of these conditions have become key in regaining muscular performance levels and to guarantee performance and economy of motion in swimming, cycling and running. The aim of this review is to provide an overview of the current findings on the pathophysiology, as well as treatment and prevention of, these conditions in compliance with clinical implications for elite triathletes. In the context of DOMS, the majority of recovery interventions have focused on different protocols of compression, cold or heat therapy, active regeneration, nutritional interventions, or sleep. The authors agree that there is a compelling need for further studies, including high-quality randomized trials, to completely evaluate the effectiveness of existing therapeutic approaches, particularly in triathletes. The given recommendations must be updated and adjusted, as further evidence emerges.

Acute and Delayed Neuromuscular Alterations Induced by Downhill Running in Trained Trail Runners: Beneficial Effects of High-Pressure Compression Garments

Introduction: The aim of this study was to examine, from a crossover experimental design, whether wearing high-pressure compression garments (CGs) during downhill treadmill running affects soft-tissue vibrations, acute and delayed responses in running economy (RE), neuromuscular function, countermovement jump, and perceived muscle soreness. Methods: Thirteen male trail runners habituated to regular eccentric training performed two separate 40-min downhill running (DHR, -8.5°) sessions while wearing either CGs (15-20 mmHg for quadriceps and calves) or control garments (CON) at a velocity associated with ∼55% of VO2max , with a set of measurements before (Pre-), after (Post-DHR), and 1 day after (Post-1D). No CGs was used within the recovery phase. Perceived muscle soreness, countermovement jump, and neuromuscular function (central and peripheral components) of knee extensors (KE) and plantar flexors (PF) were assessed. Cardiorespiratory responses (e.g., heart rate, ventilation) and RE, as well as soft-tissue vibrations (root mean square of the resultant acceleration, RMS Ar ) for vastus lateralis and gastrocnemius medialis were evaluated during DHR and in Post-1D. Results: During DHR, mean values in RMS Ar significantly increased over time for the vastus lateralis only for the CON condition (+11.6%). RE and cardiorespiratory responses significantly increased (i.e., alteration) over time in both conditions. Post, small to very large central and peripheral alterations were found for KE and PF in both conditions. However, the deficit in voluntary activation (VA) was significantly lower for KE following CGs (-2.4%), compared to CON (-7.9%) conditions. No significant differences in perceived muscle soreness and countermovement jump were observed between conditions whatever the time period. Additionally, in Post-1D, the CGs condition showed reductions in neuromuscular peripheral alterations only for KE (from -4.4 to -7.7%) and perceived muscle soreness scores (-8.3%). No significant differences in cardiorespiratory and RE responses as well as countermovement jump were identified between conditions in Post-1D. Discussion: Wearing high-pressure CGs (notably on KE) during DHR was associated with beneficial effects on soft-tissue vibrations, acute and delayed neuromuscular function, and perceived muscle soreness. The use of CGs during DHR might contribute to the enhanced muscle recovery by exerting an exercise-induced "mechanical protective effect."

Effect of Compression Garments on the Development of Delayed-Onset Muscle Soreness: A Multimodal Approach Using Contrast-Enhanced Ultrasound and Acoustic Radiation Force Impulse Elastography

BACKGROUND

Delayed-onset muscle soreness (DOMS) is one of the most common reasons for impaired muscle performance in sports. However, little consensus exists regarding which treatments may be most effective, and the underlying mechanisms are poorly understood.

OBJECTIVES

To investigate the influence of compression garments on the development of DOMS, focusing on changes in muscle perfusion and muscle stiffness.

METHODS

In this controlled laboratory study with repeated measures, muscle perfusion and stiffness, calf circumference, muscle soreness, passive ankle dorsiflexion, and creatine kinase levels were assessed in participants before (baseline) a DOMS-inducing eccentric calf exercise intervention and 60 hours later (follow-up). After DOMS induction, a sports compression garment (18-21 mmHg) was worn on 1 randomly selected calf until follow-up, while the contralateral calf served as an internal control. Muscle perfusion was assessed using contrast-enhanced ultrasound (peak enhancement and wash-in area under the curve), while muscle stiffness was assessed using acoustic radiation force impulse (shear-wave velocities). A magnetic resonance imaging scan of both lower legs was also performed during the follow-up testing session to characterize the extent of exercise-induced muscle damage. Comparisons were made between limbs and over time.

RESULTS

Shear-wave velocity values of the medial gastrocnemius showed a significant interaction between time and treatment (P = .006), with the noncompressed muscle demonstrating lower muscle stiffness values at follow-up compared to baseline or to the compressed muscle. No significant differences in soleus muscle stiffness were noted between limbs or over time, as was the case for muscle perfusion metrics (peak enhancement and wash-in area under the curve) for the medial gastrocnemius and soleus muscles. Further, compression had no significant effect on passive ankle dorsiflexion, muscle soreness, calf circumference, or injury severity, per magnetic resonance imaging.

CONCLUSION

Continuous wearing of compression garments during the inflammation phase of DOMS may play an important role in regulating muscle stiffness; however, compression garments have no significant effects on intramuscular perfusion or other common clinical assessments. J Orthop Sports Phys Ther 2018;48(11):887-894. Epub12 Jun 2018. doi:10.2519/jospt.2018.8038.

Impact of Wearing Graduated Compression Stockings on Psychological and Physiological Responses during Prolonged Sitting

We investigated the impact of wearing vs. not wearing graduated compression stockings on psychological and physiological responses in 18 healthy young people (12 men and six women) during 3 h prolonged sitting. Profiled of Mood States (POMS) scores did not show marked differences between with and without stockings. A 3 h sit significantly decreased saliva cortisol in both conditions; with no differences between conditions. Wearing stockings suppressed a subjective uncomfortable sensation (e.g., pain; fatigue; swelling) in the lower limbs, as assessed by visual analogue scale (VAS). Increase in heart rate at 1 h and 3 h was significantly greater without than with stockings. In addition, high-frequency oscillations (HF: 0.15–0.4 Hz), used as an indicator of parasympathetic nerve activity, showed higher values with than without stockings throughout the 3 h sitting period—significantly higher at 1 h. When data for both conditions were pooled pre-to-post changes in saliva cortisol were positively associated with higher uncomfortable sensations of VAS in the lower limbs and negatively associated with changes in the Vigor subscale of POMS. Collectively, these findings suggest that wearing graduated compression stockings may benefit from subjective comfort and increased parasympathetic nerve activity.

Application of Acoustic Radiation Force Impulse Elastography in Imaging of Delayed Onset Muscle Soreness: A Comparative Analysis With 3T MRI

Context: Delayed onset muscle soreness is one of the most common reasons for impaired muscle performance in sports and is associated with reduced muscle strength and frequently observed both in professional and recreational athletes. Objective: To emphasize the diagnostic value of acoustic radiation force impulse (ARFI) in imaging of delayed onset muscle soreness by comparing findings with high-resolution 3T magnetic resonance imaging T2-weighted sequences. Design: Case series. Setting: Laboratory environment. Participants: Fifteen healthy students (7 females and 8 males; mean [SD]: age 24 [4] y, height 178 [10] cm, body weight 67 [12] kg). Main Outcome Measures: ARFI values, represented as shear wave velocities of the gastrocnemius muscle and soleus muscle, as well as conventional ultrasound, high-resolution 3T magnetic resonance imaging, creatine kinase activity, extension range of the ankle joint, calf circumference, and muscle soreness were assessed before (baseline) and 60 hours after (postintervention) a standardized eccentric exercise. Results: ARFI shear wave velocity values of the gastrocnemius muscle revealed a statistically significant decrease of 19.1% between baseline (2.2 [0.26] m/s) and postintervention (1.78 [0.24] m/s); P = .01. At follow-up, the magnetic resonance imaging investigations showed intramuscular edema for the gastrocnemius muscle in all participants corresponding to a significant raise in T2 signal intensity (P = .001) and in T2-time values (P = .004). Conclusions: ARFI elastography seems to be an additional sensitive diagnostic modality in the diagnostic workup of delayed onset muscle soreness. Intramuscular shear wave velocities could represent an additional imaging marker for the assessment and monitoring of ultrastructural muscle injuries and therefore be helpful for individual training composition in elite sports.

Irisin response to downhill running exercise in humans

[Purpose]

To determine the effects of exercise-induced muscle damage, we examined irisin responses during level running (LR), with less muscle damage, and downhill running (DHR), with greater muscle damage under equivalent exercise duration and oxygen consumption (⩒O₂) conditions.

[Methods]

Fifteen healthy men (age: 21.6 ± 2.0 y, height: 170 ± 1.3 cm, weight: 64.8 ± 2.7 kg) were randomly assigned to either the LR group (n = 8) or the DHR group (n = 7). Subjects in the LR group performed treadmill running at 70% of maximum oxygen uptake (⩒O_2max) for 30 min on a 0% gradient. In contrast, subjects in the DHR group performed the same exercise on a –10% gradient. Blood samples were collected before exercise, immediately after exercise, and 1, 3, and 24 h after exercise.

[Results]

No significant interaction (group × time) or main effect of group or time was observed for changes in plasma irisin concentrations over time (P > 0.05). However, the area under the curve of plasma irisin concentrations during a 3-h post-exercise period was significantly greater in the DHR (239,197 ± 8,166 ng/mL) group than in the LR (92,293 ± 8,755 ng/ml) group (P < 0.05). The blood lactate, serum cortisol, myoglobin, and plasma interleukin-6 concentrations were significantly higher in the DHR group than in the LR group after exercise (P < 0.05 for all variables).

[Conclusion]

DHR associated with marked muscle damage promoted a greater increase in exercise-induced irisin did LR after the same duration under identical VO2 conditions.

Efficacy of wearing compression garments during post-exercise period after two repeated bouts of strenuous exercise: a randomized crossover design in healthy, active males

Background

The efficacy of wearing [a] compression garment (CG) between repeated bouts of exercise within a same day has not been fully understood. The present study determined the effect of wearing a CG after strenuous exercise sessions (consisting of sprint exercise, resistance exercise, drop jump) twice a day on exercise performance, muscle damage, and inflammatory responses.

Methods

Eleven physically active males (age, 22.7 ± 0.9 years; height, 175.7 ± 6.7 cm; body mass, 73.6 ± 10.2 kg; BMI, 23.8 ± 2.7 kg/m²) performed two trials (a randomized crossover design), consisting of the trial with either wearing a whole-body CG during post-exercise period (CG trial) or the trial with wearing a normal garment without specific pressure (CON trial). Two exercise sessions were conducted in the morning (09:00–10:00, Ex1) and afternoon (14:00–15:00, Ex2). Immediately after completing 60 min of each exercise, the subjects in the CG trial changed into a whole-body CG. Time-course changes in exercise performance (bench press power, jump performances, repeated sprint ability), blood variables (lactate, glucose, myoglobin, creatine kinase, interleukin-6, leptin), and scores of subjective feeling (fatigue, muscle soreness) were compared between the CG and CON trials before Ex1 (8:40), immediately before Ex2 (14:00, 4 h after Ex1), 4 h after Ex2 (19:00), and 24 h after the onset of Ex1 (9:00).

Results

Two bouts of exercise significantly decreased performances of counter movement jump (main effect for time: P = 0.04, F = 3.75, partial η² = 0.27) and rebound jump (main effect for time: P = 0.00, F = 12.22, partial η² = 0.55), while no significant difference was observed between the two trials (interaction: P = 0.10, F = 1.96, partial η² = 0.16 for counter movement jump, P = 0.93, F = 0.01, partial η² = 0.001 for rebound jump). Repeated sprint ability (power output during 10 × 6 s maximal sprint, 30-s rest periods between sprints) did not differ significantly between the two trials at any time points. Power output during bench press exercise was not significantly different between the two trials (interaction: P = 0.46, F = 0.99, partial η² = 0.09 for Ex1, P = 0.74, F = 0.38, partial η² = 0.04 for Ex2, P = 0.22, F = 1.54, partial η² = 0.13 for 24 h after the onset of Ex1). Serum myoglobin, creatine kinase, leptin, and plasma interleukin-6 were not significantly different between the two trials (interaction: P = 0.16, F = 2.23, partial η² = 0.18 for myoglobin; P = 0.39, F = 0.81, partial η² = 0.08 for creatine kinase; P = 0.28, F = 1.30, partial η² = 0.13 for leptin; P = 0.34, F = 1.05, partial η² = 0.12 for interleukin-6). Muscle soreness at 24 h during post-exercise period was significantly lower in the CG trial than in the CON trial for pectoralis major muscle (P = 0.04), while the value was inversely lower in the CON trial for hamstring (P = 0.047).

Conclusions

Wearing a whole-body CG during the post-exercise period after two bouts of strenuous exercise sessions separated with 4 h of rest did not promote recovery of muscle function for lower limb muscles nor did it attenuate exercise-induced muscle damage in physically active males.

Calf Compression Sleeves Change Biomechanics but Not Performance and Physiological Responses in Trail Running

Introduction: The aim of this study was to determine whether calf compression sleeves (CS) affects physiological and biomechanical parameters, exercise performance, and perceived sensations of muscle fatigue, pain and soreness during prolonged (~2 h 30 min) outdoor trail running.

Methods: Fourteen healthy trained males took part in a randomized, cross-over study consisting in two identical 24-km trail running sessions (each including one bout of running at constant rate on moderately flat terrain, and one period of all-out running on hilly terrain) wearing either degressive CS (23 ± 2 mmHg) or control sleeves (CON, <4 mmHg). Running time, heart rate and muscle oxygenation of the medial gastrocnemius muscle (measured using portable near-infrared spectroscopy) were monitored continuously. Muscle functional capabilities (power, stiffness) were determined using 20 s of maximal hopping before and after both sessions. Running biomechanics (kinematics, vertical and leg stiffness) were determined at 12 km·h⁻¹ at the beginning, during, and at the end of both sessions. Exercise-induced Achilles tendon pain and delayed onset calf muscles soreness (DOMS) were assessed using visual analog scales.

Results: Muscle oxygenation increased significantly in CS compared to CON at baseline and immediately after exercise (p < 0.05), without any difference in deoxygenation kinetics during the run, and without any significant change in run times. Wearing CS was associated with (i) higher aerial time and leg stiffness in running at constant rate, (ii) with lower ground contact time, higher leg stiffness, and higher vertical stiffness in all-out running, and (iii) with lower ground contact time in hopping. Significant DOMS were induced in both CS and CON (>6 on a 10-cm scale) with no difference between conditions. However, Achilles tendon pain was significantly lower after the trial in CS than CON (p < 0.05).

Discussion: Calf compression did not modify muscle oxygenation during ~2 h 30 of trail running but significantly changed running biomechanics and lower limb muscle functional capabilities toward a more dynamic behavior compared to control session. However, wearing compression sleeves did not affect performance and exercise-induced DOMS, while it minimized Achilles tendon pain immediately after running.