Massage Today | January, 2016, Vol. 16, Issue 01
Contributed by April Neufeld, BS, LMT; Beth Barberree, BA, RMT; Derek R. Austin, PT, DPT, MS, BCTMB, CSCS
Massage therapy increasingly is integrated into the healthcare plan for individuals suffering from a multitude of conditions.
In particular, athletes, and those people supporting the athletes, believe that massage therapy can yield many benefits that could aid the athlete biomechanically, physiologically, neurologically, and psychologically. However, when research articles were reviewed to examine the effects of massage therapy on the immune system, researchers found that the benefits were unclear. This month, the Massage Therapy Foundation’s research column reports on a literature review published in Physical Therapy in Sport (2014): Immunological effects of massage after exercise. “The purpose of this [literature review],” wrote the authors, “was to describe and review the current literature on massage and its role in modulating immune parameters when applied after intense physical activity.”
The authors searched databases (Pubmed Medline, PEDro, and Cochran) for controlled studies conducted between 1970 and 2012 using specific keywords: massage, myofascial release, acupressure, recovery, warm up, exercise-induced muscle damage, exercise, sport, immunology, and lymphocytes. And they only included studies where “massage was the main intervention, control subjects received a placebo treatment, immunological variables were measured, and all study participants were healthy people. Studies were excluded when subjects had a history of systemic disease, had less than 5 hours of physical activity each week, smoked, had been involved in intense exercise during the previous 4-months, or had a contraindication of training.” While the literature search appears thorough, the authors did not clarify why they excluded articles where participants had been involved in intense exercise.
Of the original 739 studies initially identified that examined some aspect of immunology, massage therapy, or randomized controlled trials (RTC) relating to post-exercise recovery massage, all but five studies were excluded for final review because they did not meet at least one of the inclusion criteria. “The inclusion criteria were as follows: massage is the main intervention; control subjects receive a placebo treatment; immunological variables are measured, and all study participants are healthy individuals.” This last inclusion, that study participants must be healthy, is of particular interest because often research is performed on populations with health problems and yet many massage therapists report their clients are mostly healthy individuals.
“The results of this review suggest that massage may exert an influence on immune parameters, especially when applied after high-intensity exercise,” wrote the researchers. Some evidence suggested that massage helps support immune system response by impacting the levels of proinflammatory cytokines (important in the anti-inflammatory response). For example, in a study where massage was performed on Quadriceps, cytonkine levels s were found to be higher in the non-massaged Qquadriceps than in the treatedmassaged legQuadriceps. Since exercise can cause a potentially damaging inflammatory response, decreasing the levels of proinflammatory cytokines could be beneficial. The authors also wrote of the speculation that massage therapy induces a parasympathetic response and so “improvements in local circulation may indirectly reduce the proinflammatory cytokines.” However, since much of this research is performed on only a single body part (e.g. one leg), it is difficult to assess the overall role of massage therapy on the parasympathetic system.
Two studies were compared that described the movement of neutrophils towards the focus of post exercise inflammation. But since each study examined different sized muscles, and each had different intensities and duration of exercise prior to the intervention, the researchers concluded that it is difficult to make generalizations about the effects of massage on neutrophil count without further research.
Despite the impact on a variety of immune system constituents, it was noted that only a reduced IgA level is associated with increased risk of infection. The review yielded only one study on the impact of post exercise massage on IgA levels, and that study found that significant recovery of IgA levels occurs following massage, especially in females.
Also notable to readers, may be that three of the five studies in the review found “no robust evidence of an immunological improvement after massage” (Hilbert, Sforzo, Swensen, 2003; Smith et al., 1994; Stock, Baum, Rosskopf, Schober, Weiss, Liesen, 1996). In contrast, only two studies supported the immunological benefits (Arroyo-Morales et al., 2009; Crane et al., 2012).
Systematic reviews can be useful for readers to get a broader understanding of a particular topic, but can raise more questions than they answer. Readers will recognize that there are many factors that can influence the results of a study: sample size, type of massage therapy performed, timing of the intervention, type of exercise the subjects were engaged in, and duration and intensity of the exercise. Of the five studies examined, all had different sample sizes. All studies used healthy and active subjects but not all studies examined the same kind of exercise or frequency of the physical activity. Each study had the massage therapy application applied to different body parts. Additionally, the review examined four studies that indicated there were greater immunological effects when the massage therapy was applied following a 2-hour delay post exercise. “The differences in training mode and intensity may have produced corresponding variations in the immunosuppressive effects obtained, influencing evaluations of the recovery achieved by massage,” wrote the researchers. “The data in this review suggest that massage may have a more relevant effect on the immune response after exercise with a higher cardiovascular demand. However, further research is required to confirm this possibility.”
The researchers report there were several weaknesses in the studies selected for the review. One was that there was no information on any adverse effects that could have indicated complications with massage therapy as an intervention. Sports massage therapists might be tempted to read the information about the 2-hour delay and think that they should use that model on the athletes they work with. However, it is important to remember that while the subjects studied were young and healthy, none of them participated in professional sports or were elite athletes who practiced at moderate/high-intensity levels of physical activity.
The authors of this review clearly pointed out that a main limitation of the studies was that although some reported cell count changes, further research is needed to understand if these cells are simply relocating in the body as part of an immune response or actually proliferating.
Systematic reviews are excellent ways for readers to get a broad view of various studies examining a single topic. And as researchers explore topics before beginning new studies, a review is especially helpful to inform new projects by seeing what studies could be improved upon.
For more information on other reviews that have been done on massage therapy, please read the Massage Therapy Foundation review article archives, read accepted MTF Research Grant abstracts, or search PubMed for massage therapy studies.
The Massage Therapy Foundation continues to support and promote research as seen in this month’s review. Registration is now open for the 2016 International Massage Therapy Research Conference (IMTRC) that will be held in Seattle, Washington, May 12-15. Registration information as well as conference updates are now available on the website at www.massagetherapyfoundation.org.
- Tejero-FernÃ¡ndez V, Membrilla-Mesa M, Galiano-Castillo N, Arroyo-Morales M. Immunological effects of massage after exercise: A systematic review. Phys Ther Sport. 2015 May;16(2):187-92. doi: 10.1016/j.ptsp.2014.07.001. Epub 2014 Jul 21. Review. PubMed PMID: 25116861.