Does a foam roller increase strength?

When you look around a gym, you almost certainly see someone engaging in a self-massage session in order to prepare their muscles before (sometimes after) a workout or to try to sorely treat their trigger points, etc.

The most common technique for myofascial release is foam rolling, which consists of using a Foam Roller (RM) Or plastic to massage muscles before exercising.

Does this practice actually increase performance when used as part of a warm-up? At what pressure or “force” should the roller be used?

The study we're about to decode looked at how using low, medium or high force of a massage roller on the quadriceps can increase range of motion or leg strength and power.⁽¹⁾.

Decode the study

Participants

There were 16 people in this study: 8 men and 8 women. All participants were young, healthy and physically active, whether in strength training or aerobic training. To be included, volunteers had to complete at least three training sessions per week of at least 20 minutes and have no experience with foam rolling or “self-myofascial release.” Table 1 summarizes these details and other characteristics.

Definition and determination of load/force

Participants performed this study after four visits to the research center, the first to familiarize themselves with the testing procedures and the other three to test a specific parameter (mild MR, moderate MR or high MR). At the beginning of the experiment, subjects performed full sets of MRIs and added weight plates on either side of the ends of the cylinder until a maximum value of “10” on a 0 to 10 relative scale of perceived pain (DP) was reached. After passing for 4 seconds on the thigh muscles.

This made it possible to calculate the loads used for each session. Regardless of what participants considered a PD of 10/10, 50% of this maximum was used as load for light RM, 70% for moderate RM, and 90% for high RM.

The researchers also calculated the average force applied by RM in each case, and expressed this force either in absolute terms (newtons) or as a percentage relative to the person's body mass.

Furthermore, subjects rated their average PD during each session, resulting in average PDs of 3.9, 6.2, and 8.2 out of 10 for mild MRI, medium MRI, and high MRI, respectively. This information is shown in Table 2.

Test session protocol

In each testing session, participants completed five minutes of low-intensity cycling and then performed tests on the following parameters:

• Active knee flexion range.
• Passive knee flexion range.
• Two jumps with maximum amplitude on one leg (S.J.).
• Leg extensions with maximum isometric contraction (CIM).
• Two leg curls with maximum isometric contraction.

CIM measurements consisted of measuring total force and force during the first 200 ms (F 200) of the effort.

Next, participants sat quietly for 10 minutes before testing the five parameters again, but this time with only one repetition of the ICD test.

Then RM intervened. During this, individuals utilized 3 series of 60-second RM with low, medium or high intensity exercise. During each 60-second set, a full roll of the quadriceps was done every 4 seconds; Thus, 15 paragraphs were implemented for each series. Ranges of knee flexion and extension as well as single leg hops were tested between each MR series.

Evaluation of all parameters (again using a single ICD test of flexion and extension) was performed immediately after the third MR series. Finally, all analyzes were performed again after a 10-minute rest. A full description of the methodology is provided in the timeline below.

Results

Range of motion on positive and negative flexion

Active range of motion increased significantly from pre- to post-intervention (+7.0%, p = 0.029, effect size = 2.25), and also 10 minutes after the intervention (+6.9% p = 0.026, effect size = 2.38). Likewise, passive range of motion increased immediately after the intervention (+15.4%, p<0.001, effect size =3.73) and after 10 minutes (+11.9%, p<0.001, effect size =2.90).

There was a small effect size (0.43) in favor of low RM over medium RM and a moderate effect size (0.55) in favor of low RM over high RM for an increase in passive range of motion between pre- and post-intervention. These effect sizes indicate a greater increase in passive range of motion with lower RM compared to the others.

Single leg hop and isometric contraction force

There was no significant change in jumping in any condition (P>0.05).

CIM strength was lower in the second pre-intervention test (conducted 10 minutes after the first pre-test, -6.0%, p<0.038, effect size = 1.74) for knee flexion, and F 200 during knee flexion decreased by 11.8% immediately after Intervention compared to the first pretest.

For the CIM knee extension, there was a mean decrease in strength of -4.8% between the first pretest and the second pretest. F 200 knee flexion also decreased after the intervention.

My comments and interpretations

These results clearly confirm that RM is an effective way to increase range of motion without resulting in a decrease in maximal strength. So, yes, there was a decrease in knee flexion strength after the operation; But he already had a decrease in strength during the second pretest before the intervention. It is therefore possible that this reduction was simply due to fatigue following the five efforts already implemented at CIM. Therefore, based on his data, it does not appear that RM had any effect on performance.

The current study therefore supports a previous systematic review that concluded that RM and all forms of myofascial release have no effect (positive or negative) on performance.⁽²⁾.

However, the strength results should not surprise you if you know the mechanical reasons for decreased performance after static stretching. In short, maintaining a stretched position reduces the stiffness of the musculotendinous unit, compromising the beneficial effects of the extension reflex.⁽³⁾Prolonged stretching reduces performance more than short stretching⁽⁴⁾.

When you think about foam rolling, there is no constant “hold” in the stretched position (at least not for a long period of time); Rather, there is a continuous rolling movement. Therefore, from a mechanical point of view, there should be no drop in performance.

However, I would like to draw your attention to the fact that if RM is used for too long, it can indirectly harm performance.

This theoretical reduction is not necessarily due to mechanical reasons, but it stands to reason that if you spend 20 to 30 minutes doing this work before exercise, fatigue may set in.

Finally, should you use any type of myofascial release activity during your warm-up? In the words of Leonid and Chen (2017)⁽⁵⁾“There is no evidence that myofascial release is effective in improving muscle strength or performance and it cannot be recommended in a training routine for activities requiring strength or to improve performance.”

Finally, one of the most important findings of this study is that low MR increases range of motion more than medium MR and high MR.

Therefore, when using myofascial release techniques, you do not need to experience severe pain (low MR = 3.9/10 DP) to achieve a significant increase in mobility.

What to remember

People who have limited mobility in a particular joint can use this technique to increase their range of motion without reducing their performance. It is important to remember that the effects are evident even when rolling pressure is low.