Authors: Therabody Scientists: Tim Roberts, MSc; Rachelle Reed, PhD, MS, ACSM-EP; Kyle Silvey, PhD, CSCS; Michelle Darian, MS, MPH, RD, LDN 

Athletes and fitness enthusiasts are always looking for ways to recover faster and get back into practice sooner and stronger. Pneumatic compression devices are a popular tool to lean on for just that.  

These devices offer many science-backed benefits, including decreasing soreness, pain, and muscle stiffness while improving range of motion. [1 – 4] Researchers of a new study put Therabody’s ® Recovery Air 3 PRO pneumatic compression boots to the test to see if they enhanced recovery and subsequent exercise performance in a cycling workout.  

Overall, using Therabody’s pneumatic compression boots improved perceived fatigue and hematocrit levels (a proxy for recovery). But, the study results, specifically the effects of compression boots on subsequent, short-term performance, were nuanced. [5] 

Let’s dive into the study, starting with the science behind pneumatic compression, and what this novel research adds to our understanding of how pneumatic compression boots may expedite recovery.  

How Pneumatic Compression Works  

Pneumatic compression is a therapy that uses air pressure delivered via a garment that fits on the body’s limbs, typically through inflatable boots or arm cuffs. The mechanical pumping and the subsequent inflation and deflation of the garment squeeze the limb to help move blood through the veins and toward the heart and stimulate the lymphatic system to filter waste products. [6] 

Pneumatic compression garments can have different chambers, allowing varying degrees of pressure to be applied to different parts of the limb. Intermittent sequential pneumatic compression (ISPC), the technology used in Therabody’s compression boot products, means that there is a sequential rhythm of timing to the pressure. This mechanical inflation and deflation mimics the body’s natural muscle pump action, which promotes blood flow and circulation back to the heart. [7]  

ISPC promotes circulation in the treatment area. It increases the filtering of waste products from the blood that can accumulate during exercise into the lymph. The subsequent pumping of the lymphatic system gets rid of these waste products. This is beneficial for outcomes related to recovery (like improving flexibility and swelling). [8]  

Theoretically, improving and expediting recovery can have downstream effects on subsequent athletic performance. If you recover faster, your body can perform harder on the next exercise bout. To date, few studies have measured performance following ISPC use and haven’t found immediate significant improvements. [9, 10]  

Led by Dr. Iker Garcia Alday at the University of Barcelona, this novel study aims to quantify the impact of ISPC on both recovery and subsequent immediate performance after repeated cycling sprint exercises. “Previously, we demonstrated that ISPC enhances cardiovascular recovery after high-intensity exercise. Here, we evaluated the effects of ISPC in acute cycling performance, hemodynamics, and psychological recovery," says Dr. Alday. 

About the Study 

Researchers hypothesized that the use of ISPC would help move fluid away from the legs after intense exercise, leading to the recovery of blood concentrations (measured by hematocrit levels), less leg swelling (measured by leg water concentration), and more power in a subsequent workout compared to rest alone.  

To test that, they recruited a total of 16 participants (7 female and 9 male) to take part in two trials of fatiguing cycling sprints, seven days apart. On average, females were 33 and males were 26 years old, and all participants were healthy and trained, regularly engaging in high-intensity interval exercise at least three sessions per week. 

Here are the steps participants took each time they visited the lab:  

Results Showed ISPC May Improve Hematocrit Levels and Perceived Recovery 

Analyses revealed that ISPC showed some promising results for recovery. 

Pneumatic Compression Improved Post-Exercise Hemodilution 

Following recovery from ISPC, the post-exercise hemodilution response improved. What does this mean for recovery?  

Human blood homeostasis is characterized by a trade-off between high hemoglobin levels to bind to oxygen and relatively low blood viscosity levels to allow rapid blood flow. 

Exercise causes physiological changes that shift water, electrolytes, and other substances from the muscles and tissues into the bloodstream (or cause water loss through sweat). Changes in fluid decrease the concentration of red blood cells found in the blood — hemodilution. [11] As red blood cells are responsible for carrying oxygen and nutrients to tissues, excessive hemodilution — or hemodilution that doesn’t resolve quickly — may impair recovery because oxygen and nutrients aren’t as readily available to help sore muscles recover.  

“Hematocrit levels in the ear lobe are a marker of the hemodynamic activity. They indicate the extent to which blood flow delivers nutrients and removes metabolites from the muscle," explains Dr. Alday.  

In this study, ISPC did a better job than passive recovery alone at improving hemodilution after exercise.  

Perceived Recovery Improved in the Pneumatic Compression Group 

Participants also reported on their rate of perceived exertion (RPE) at three time points: after the exercise, recovery, and post-recovery exercise session. There was no significant difference in perceived exertion after each recovery method, indicating both groups experienced the same level of exhaustion during exercise.  

There were significant differences in perceptual fatigue felt after the first and second exercises: both groups reported feeling more tired after the first (and longer) exercise than the second. 

They also rated their total quality recovery (TQR) after completing their recovery method. Participants felt more recovered after the ISPC recovery than passive rest. This shows that ISPC more effectively promoted perceived recovery after exercise than the control condition. 

No Differences in Power or Leg Water Concentrations Were Observed Between Recovery Methods 

Researchers hypothesized that ISPC would increase power and decrease leg water concentrations following ISPC treatment. The study results actually differed from this hypothesis.  

Power was the primary metric used to assess performance in this study. Researchers measured cycling power output in Watts (W). The results showed that there was no significant difference in average power output following the ISPC recovery compared to a passive recovery.  

The study also found no major difference in the amount of water in the legs between ISPC and passive recovery. After exercise, high fluid levels in the legs can impair recovery and performance. [12] 

While not statistically significant, ISPC tended to help reduce leg swelling, suggesting this therapy may help move fluid out of the legs more effectively. That said, further research with larger sample sizes is needed to better understand this finding.  

Does ISPC Support Recovery?  

The study found that ISPC is a beneficial tool to support recovery after repeated bouts of cycling exercise. ISPC may help you feel more recovered immediately after high-intensity exercise.  

Longer recovery periods may allow more time for the body to heal and for any benefits of the ISPC treatment to become more evident. This could potentially reveal differences in performance or recovery that weren’t apparent in the short term in this study. 

A previous study shows that using Therabody’s RecoveryAir boots immediately after a workout kickstarts cardiovascular recovery, allowing for a faster return to pre-exercise blood pressure and improved cardiac output and peripheral vascular resistance. [13] 

So, there are benefits to starting ISPC therapy right after an intense physical feat. It’s important to note that many factors influence athletic performance, including training regimen, nutrition, sleep, stress, and hydration. [14] 

Studies with a longer recovery time, more regular use of ISPC, and those that account for additional characteristics that impact performance may be needed to understand their impact on performance.  

“After this short-term intervention, we conclude that ISPC improves relevant physiological and psychological markers in athletes. Future studies are needed to evaluate the effects of ISPC, both acutely and long-term, in athletes," concludes Dr. Alday. 

Key Takeaways 

References: