Effects of Foam Rolling Duration on Tissue Stiffness and Perfusion: A Randomized Cross-Over Trial

Effects of Stretching or Strengthening Exercise on Spinal and Lumbopelvic Posture: A Systematic Review with Meta-Analysis

BACKGROUND

Abnormal posture (e.g. loss of lordosis) has been associated with the occurrence of musculoskeletal pain. Stretching tight muscles while strengthening the antagonists represents the most common method to treat the assumed muscle imbalance. However, despite its high popularity, there is no quantitative synthesis of the available evidence examining the effectiveness of the stretch-and-strengthen approach.

METHODS

A systematic review with meta-analysis was conducted, searching PubMed, Web of Science and Google Scholar. We included controlled clinical trials investigating the effects of stretching or strengthening on spinal and lumbopelvic posture (e.g., pelvic tilt, lumbar lordosis, thoracic kyphosis, head tilt) in healthy individuals. Effect sizes were pooled using robust variance estimation. To rate the certainty about the evidence, the GRADE approach was applied.

RESULTS

A total of 23 studies with 969 participants were identified. Neither acute (d = 0.01, p = 0.97) nor chronic stretching (d=-0.19, p = 0.16) had an impact on posture. Chronic strengthening was associated with large improvements (d=-0.83, p = 0.01), but no study examined acute effects. Strengthening was superior (d = 0.81, p = 0.004) to stretching. Sub-analyses found strengthening to be effective in the thoracic and cervical spine (d=-1.04, p = 0.005) but not in the lumbar and lumbopelvic region (d=-0.23, p = 0.25). Stretching was ineffective in all locations (p > 0.05).

CONCLUSION

Moderate-certainty evidence does not support the use of stretching as a treatment of muscle imbalance. In contrast, therapists should focus on strengthening programs targeting weakened muscles.

Effects of foam rolling on hamstrings stiffness in damaged and non-damaged muscle states

Introduction: The aim of this study was to examine the effects of foam rolling (FR) on hamstring muscles stiffness in both non-damaged and exercise-induced muscle damage (EIMD) states, using shear wave ultrasound elastography to measure changes in shear modulus. Methods: Fourteen healthy adults (25.5 ± 4.7 years) participated in a within-participant repeated measures design, with a 2-minute FR intervention applied on one leg and contralateral leg serving as a control. The damaging protocol encompassed maximal eccentric knee extensions performed on an isokinetic dynamometer and the Nordic hamstring exercise, consisting of 3 sets of 10 and 6 repetitions, respectively. Measurement were taken at baseline and then 1 h, 24 h and 48 h after the damaging protocol. Results: The results indicated no significant time × leg interaction for shear modulus in biceps femoris, semimembranosus, and semitendinosus muscles in both non-damaged and damaged states. Notably, there was a significant increase in biceps femoris (p = 0.001; η2 = 0.36) and semitendinosus (p < 0.001; η2 = 0.44) shear modulus after EIMD, but no significant differences were found between the FR and control leg, which was also the case for muscle soreness, range of motion, and passive resistive torque (p = 0.239-0.999 for interactions). Discussion: The absence of significant changes post-FR intervention suggests a limited role of short-duration FR in altering muscle stiffness during recovery from EIMD. These findings contribute to the understanding of FR's role in muscle recovery. Although this was not directly investigated, our results suggest a predominance of central mechanisms rather than direct mechanical modifications in muscle properties. This research highlights the necessity for additional investigations to explore how FR interventions influence muscles in different states and to elucidate the mechanisms underlying these influences.

Acute effects of foam rolling on ankle dorsiflexion and squat exercise patterns in extreme conditioning program practitioners: A randomized clinical trial

BACKGROUND/OBJECTIVES

Joint and muscle overloads commonly occur in extreme conditioning programs (ECP), which require great physical fitness for their practice. For its execution, good functional performance, mobility and adequate movement patterns are required. The fascial system plays a fundamental role in performance in ECP and one of the techniques used to improve joint mobility and movement pattern is the self-myofascial release using a foam roller (FR). Our objective of this study was to evaluate the effect of FR in ankle dorsiflexion (DF) range of motion (ROM), assessed with the Lunge Test, and also in the squat movement pattern, assessed using the Technique smartphone application, in ECP practitioners.

METHODS

The study was carried out with 18 ECP practitioners who practiced for over four months and had a mean age of 30.94 years. The participants were randomized and allocated into two groups: control and intervention. The FR was self-applied bilaterally in the sural triceps region for 90 seconds. Tests to assess DF ROM and squat movement pattern were applied before and immediately after using FR (intervention group) or after three-minute rest (control group).

RESULTS

The use of the FR promoted an immediate increase in ankle DF ROM during the Lunge Test and during the squat and a decrease in dynamic knee valgus during the squat.

CONCLUSION

The FR can be used as a tool for an acute increase in DF ROM and a decrease in dynamic knee valgus, having a positive impact in improving movement patterns.

Effects of foam rolling on vastus intermedius and lateralis microvascular blood flow

INTRODUCTION

Foam Rolling (FR) as a technique of self-massage has become a widely used intervention in clinical and sports practice. It is assumed that FR leads to an increased intramuscular microvascular blood flow (MBF), and therefore is commonly recommended as a warm-up or regeneration method. However, no data validate the effects of FR on MBF. This study aimed to assess whether FR increases intramuscular MBF using contrast-enhanced ultrasound (CEUS).

METHODS

Ten healthy athletes performed a standardized FR intervention applied to the lateral thigh (3 sets: 45 s FR, 20 s rest). Intramuscular perfusion was determined by CEUS under resting conditions (t0), immediately (t1), and 30 min (t2) after the intervention. Peak enhancement (PE), wash-in rate (WiR), and wash-in perfusion index (WiPI) were evaluated as quantitative perfusion parameters in vastus lateralis (VL) and intermedius (VI) muscle separately via regions of interest mapping.

RESULTS

Immediately after the intervention (t1), perfusion parameters showed a non-significant decrease in VL (p = 0.3; PE: -32.1%, WiPI: -29.6%, WiR: -50.4%) and VI (p = 0.4; PE: -10.3%, WiPI: -6.4%, WiR: -35.6%). A non-significant decrease was found at t2 in VL (p = 0.2; PE: -34%, WiPI -33.9%, WiR -61.2%) and VI (p = 0.2; PE -17.6%, WiPI -13.8%, WiR -43.2%).

CONCLUSIONS

The common assumption of intramuscular MBF improvement due to FR could not be confirmed for up to 30 min after the intervention. If an increase in intramuscular metabolism or MBF is intended, we recommend that alternative methods (i.e., traditional warm-up) should be preferred.

Immediate Effects of Foam Roller and Stretching to the Lead Hip on Golfers Swing: A Randomized Crossover Trial

Golfers with decreased range of motion (ROM) of their leading hip internal rotation (IR) have increased lumbar rotation ROM and load. This study investigated the effects of foam roller (FR) applied to their leading hip muscles combined with stretching to the leading hip together with lumbar rotation ROM during the golf swing. The study design was a crossover design. Subjects were allocated to one of two groups comprising FR and dynamic stretching (FR + DS) or practice swing. Motion analysis was used to evaluate hip and lumbar angles during the golf swing. Data were compared using analysis of variance with Bonferroni correction using paired t-test's post hoc. The association between lead hip IR angle and lumbar spine left rotation (Lrot) angle was investigated using correlation analysis. Lead hip IR ROM during the golf swing was significantly greater in the FR + DS group (p = 0.034). The FR + DS group showed a moderate negative correlation between lead hip IR ROM and lower lumbar spine Lrot ROM during the golf swing (r = -0.522). The application of FR + DS might be useful to increase lead hip IR angle during the golf swing. Moreover, the application of FR + DS improves lead hip IR angle and may decrease lumbar spine rotation.

Are Acute Effects of Foam-Rolling Attributed to Dynamic Warm Up Effects? A Comparative Study

Over the last decade, acute increases in range of motion (ROM) in response to foam rolling (FR) have been frequently reported. Compared to stretching, FR-induced ROM increases were not typically accompanied by a performance (e.g., force, power, endurance) deficit. Consequently, the inclusion of FR in warm-up routines was frequently recommended, especially since literature pointed out non-local ROM increases after FR. However, to attribute ROM increases to FR it must be ensured that such adaptations do not occur as a result of simple warm-up effects, as significant increases in ROM can also be assumed as a result of active warm-up routines. To answer this research question, 20 participants were recruited using a cross-over design. They performed 4x45 seconds hamstrings rolling under two conditions; FR, and sham rolling (SR) using a roller board to imitate the foam rolling movement without the pressure of the foam rolling. They were also tested in a control condition. Effects on ROM were tested under passive, active dynamic as well as ballistic conditions. Moreover, to examine non-local effects the knee to wall test (KtW) was used. Results showed that both interventions provided significant, moderate to large magnitude increases in passive hamstrings ROM and KtW respectively, compared to the control condition (p = 0.007-0.041, d = 0.62-0.77 and p = 0.002-0.006, d = 0.79-0.88, respectively). However, the ROM increases were not significantly different between the FR and the SR condition (p = 0.801, d = 0.156 and p = 0.933, d = 0.09, respectively). No significant changes could be obtained under the active dynamic (p = 0.65) while there was a significant decrease in the ballistic testing condition with a time effect (p < 0.001). Thus, it can be assumed that potential acute increases in ROM cannot be exclusively attributed to FR. It is therefore speculated that warm up effects could be responsible independent of FR or imitating the rolling movement, which indicates there is no additive effect of FR or SR to the dynamic or ballistic range of motion.