INFLUENCE OF AN ACUTE BOUT OF SELF-MYOFASCIAL RELEASE ON KNEE EXTENSION FORCE OUTPUT AND ELECTRO-MECHANICAL ACTIVATION OF THE QUADRICEPS

Self-Massage Acute Effects on Pressure Pain Threshold, Muscular Electrical Activity, and Muscle Force Production: A Systematic Review and Meta-Analysis

ABSTRACT

Furlan, MR, Machado, E, Petter, GdN, Barbosa, IM, Geremia, JM, and Glänzel, MH. Self-massage acute effects on pressure pain threshold, muscular electrical activity, and muscle force production: a systematic review and meta-analysis. J Strength Cond Res 38(3): 620-635, 2024-Self-massage (SM) is often used in physiotherapy and sports training programs. However, the SM acute effects on pressure pain threshold (PPT), muscle electrical activity (MEA), and muscle force production remain unclear. A meta-analytical review was performed to verify the SM acute effects on neuromuscular responses in healthy adults or athletes. The review (CRD42021254656) was performed in the PubMed, Web of Science, and Embase databases. A synthesis of the included studies was performed, and both the risk of bias and the evidence certainty level were assessed through the PEDro scale and Grading of Recommendations Assessment, Development, and Evaluation approach, respectively. Nineteen studies were included, 5 evaluated the PPT, 7 the thigh muscles' MEA, and 15 the lower-limb strength. The SM application induces moderate increases in quadriceps' PPT (5 studies; standardized mean difference [SMD]: 0.487; 95% CI 0.251-0.723; p < 0.001; I2 = 0%). We found no SM effects on the hamstrings and plantar flexors' MEA. Also, we observed small increases in knee extensors' concentric torque (2 studies; SMD: 0.288; 95% CI 0.088-0.489; p = 0.005; I2 = 0%), without effects in isometric muscle strength, eccentric torque, and rate of force development. Grading of recommendations assessment, development, and evaluation analysis showed high and low certainty levels for the SM effects on quadriceps' PPT and muscle strength, respectively. Self-massage pressure-volume application seems to be a determining factor in inducing changes in these parameters, and it may vary among the treated muscles, where a higher pressure-volume application is required for increasing knee flexors and plantar flexors' PPT and strength. Thus, new studies with better methodological quality should be performed to strengthen this evidence.

Effects of External Abdominal Pressure Support on Dynamic Balance: A Randomized Crossover Study

Abdominal pressure is vital in protecting the lumbar spine and controlling postural balance. Dynamic balance is associated with movement stability, adaptation to load, and reduced injury risk. Although trunk stability has been examined using belts and braces, the effects of external abdominal pressure support (APS) on balance control remain unknown. In this study, we aimed to determine the effects of external APS on dynamic balance. Overall, 31 young adults participated in this randomized crossover study. External APS was provided using a device that could be pressurized and decompressed by inflating a cuff belt wrapped around the trunk. The modified Star Excursion Balance Test was performed under external APS and non-APS conditions. The maximum anterior, posterolateral, and posteromedial values normalized to the spinal malleolar distance and their respective composite values were compared between the two conditions with and without APS. Posterolateral, posteromedial, and composite values were significantly higher in the APS condition than in the non-APS condition (p < 0.001). The external APS was effective in immediately improving dynamic balance. Furthermore, APS was effective in dynamic balance control as it improved stability during anterior trunk tilt, which displaces the center of gravity forward.

Foam Rolling Acute Effects on Myofascial Tissue Stiffness and Muscle Strength: A Systematic Review and Meta-Analysis

ABSTRACT

Glänzel, MH, Rodrigues, DR, Petter, GN, Pozzobon, D, Vaz, MA, and Geremia, JM. Foam rolling acute effects on myofascial tissue stiffness and muscle strength: a systematic review and meta-analysis. J Strength Cond Res 37(4): 951-968, 2023-Foam rolling (FR) is widely used in rehabilitation and physical training. However, the effects of FR on myofascial tissue stiffness and muscle strength remain unclear. This study aimed to perform a systematic review with meta-analysis of trials that tested the FR acute effects during warm-up on the myofascial tissue stiffness and muscle strength in healthy adults or athletes. This systematic review (CRD42021227048) was performed according to Cochrane's recommendations, with searches performed in PubMed, Web of Science, Embase, and PEDro databases. Syntheses of included studies' data were performed, and the PEDro scale was used to assess the methodological quality of the studies. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluations approach. Twenty included studies assessed trunk and thigh fascial tissue stiffness, and thigh and calf muscle stiffness, whereas muscle strength was assessed in the knee extensors and flexors, and plantar flexors muscles. Qualitative analysis showed decreases in fascial ( n = 2) and muscle ( n = 5) stiffness after FR. However, the meta-analysis showed no effects of FR on myofascial tissue stiffness. Both qualitative and quantitative analyses showed no effects of FR on isometric muscle strength, eccentric torque, and rate of force development. However, the knee extensor concentric torque increased after FR. Foam rolling increases the knee extensor concentric torque, but it does not acutely change the myofascial tissue stiffness and isometric muscle strength. However, evidence of these studies provides low certainty to state that FR does not change these parameters. Therefore, high methodological quality studies should be performed to better ascertain the effects of FR on the myofascial tissue stiffness and muscle strength.

Effects of traditional stretching versus self-myofascial release warm-up on physical performance in well-trained female athletes

OBJECTIVE

The purpose of this study was to compare the acute effects of self-myofascial release (SMR) versus traditional stretching used as a part of warm-up on physical performance in well-trained female athletes.

METHODS

Twenty-three participants (age, 21.8±1.73 years; experience in sport, 114.8±30.5 months) were recruited. Isokinetic peak torque and muscle endurance ratio were measured during knee extension and flexion at 60°/s and 180°/s. Jump height, reactive strength index, and leg stiffness were measured using a jump mat during a counter-movement jump. Hamstring flexibility was measured using a sit-and-reach test. Three interventions were performed by all athletes randomly within 72 hours intervals.

RESULTS

The jump height and hamstring flexibility test scores improved significantly more after dynamic stretching (DS) as compared to SMR and static stretching (SS). The DS and SMR exercises were more effective than the SS exercises in terms of right and left knee muscle isokinetic strength both at 60°/s, and 180°/s. With regard to keeping muscular endurance ratio (%), SS exercises were found more effective than DS and SMR exercises for only the right knee at 180°/s, but not left knee muscle.

CONCLUSION

Dynamic stretching and SMR showed better flexibility, strength, and jump performance than SS. Trainers and players may replace SS with DS and SMR to acutely improve muscle power, strength, and flexibility.

Self-Myofascial Release of the Foot Plantar Surface: The Effects of a Single Exercise Session on the Posterior Muscular Chain Flexibility after One Hour

This study evaluated the effects of a single exercise session of Self-Myofascial Release (SMR) on the posterior muscular chain flexibility after one hour from the intervention. Thirty-six participants performed SMR using a rigid ball under the surface of both feet. Participants were tested with the Sit and Reach (S&R) test at four different times: before (T0), immediately after (T1), 30 (T2), and 60 (T3) minutes after the SMR intervention. The sample (n = 36) was categorized into three groups: (1) flexible, (2) average, and (3) stiff, based on the flexibility level at T0 (S&R values of >10 cm, >0 but <10 cm and <0 cm, respectively). For the whole sample, we detected significant improvements in the S&R test between the T1, T2, and T3 compared to T0. The stiff group showed a significant (p < 0.05) improvement between T1−T2 and T1−T3. Results were similar between the average group and the whole sample. The flexible group did not show any significant difference (p > 0.05) over time. In conclusion, this investigation demonstrated that an SMR session of both feet was able to increase posterior muscular chain flexibility up to one hour after intervention. Considering that a standard training session generally lasts one hour, our study can help professionals take advantage of SMR effects for the entire training period. Furthermore, our results also demonstrate that physical exercise practitioners should also assess individuals’ flexibility before training, as the SMR procedure used in this work does not seem necessary in flexible individuals.

The Effect of Self-Myofascial Release on the Pennation Angle of the Vastus Medialis Oblique and the Vastus Lateralis in Athletic Male Individuals: An Ultrasound Investigation

Background

Maintenance of patellar stability requires a balance between the vastus medialis oblique (VMO) and the vastus lateralis (VL). The imbalance between these muscles is thought to be implicated in the etiology of patellofemoral pain (PFP). Where there is hypertrophy of the VL in PFP patients, self-myofascial release (SMR) may be utilized for its management. However, there is no current evidence regarding SMR and its effects on VMO and VL architecture. The aim of this study, therefore, was to use ultrasound to gain further understanding of the effects of a program of SMR on the fiber angles of the VMO and VL.

Hypothesis

There will be a significant decrease in the pennation angles of the VMO and VL after seven weeks of SMR using a foam roller.

Study Design

Cohort Study.

Methods

Twenty-five young, athletic, male participants were recruited to use a foam roller, along the full length of both anterior thighs, three times weekly, on three separate days, for seven weeks. Ultrasound was used to determine the initial and final VMO and VL pennation angles on both limbs. One eligible participant was chosen as an intra-rater control and did not partake in the SMR regimen.

Results

There was a statistically significant (p < 0.001) decrease in the pennation angles of the VMO and VL after the SMR regime. Mean combined right and left VL angle change was -6.65° (-18% mean change) and the mean combined right and left VMO angle change was -7.65° (-11.5% mean change). A weak negative correlation was found between initial VMO fiber angle and the angle change (Rsquared = -0.21), as well as moderate negative correlation for the VL (Rsquared = -0.51).

Conclusion

A program of SMR on the anterior thighs of young, asymptomatic males resulted in changes to the fiber angles of both the VMO and VL. There was a significant decrease in pennation angle after seven weeks of SMR using a foam roller.

Body Balance after Fascial Therapy in Athletes with Soft Lower Limb Muscle Injuries

Background: Most injuries in competitive sports are due to overstrain and excessive muscular and fascial tension. This study aimed to assess the effects of a single session of fascial therapy on balance and lower limb weight-bearing in professional athletes following a lower limb soft-tissue injury. Methods: A pedobarographic platform was used to assess the weight-bearing on both lower limbs and corporal balance. A total of 41 athletes with an acute soft-tissue injury involving the quadriceps femoris muscle were included in the study. Each patient underwent myofascial therapy in the injured limb only. The therapy was intended to release tension and improve proprioception. Results: The injured and healthy limbs showed significant asymmetry in body weight distribution. Before treatment, the patients bore less weight on the injured limb than on the healthy limb. After fascial therapy, eyes-closed tests showed an improved weight distribution symmetry between the two lower limbs. There were no significant differences in the values of the evaluated balance parameters between those measured at baseline and those measured after the therapy, measured after the rehabilitation session. Conclusions: A single fascial therapy session has a beneficial effect on corporal balance in runners with an injured lower limb.