Studies Spotlight Gains in Physical Activity and Function after Bariatric Procedures

By Thomas Crocker
Thursday, December 1, 2016
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A review of studies by researchers in the United Kingdom and Australia finds patterns of improvement in physical activity and ability 12 months after bariatric surgery.

The notion that physical activity improves following weight-loss surgery is not new to clinicians. A literature review by French researchers published in the journal Obesity Reviews in 2011, for example, noted increases in physical activity after surgery based on patient self-assessments. Until recently, however, objective data about postoperative physical activity and function were lacking, according to Louisa Herring, PhD, researcher in physical activity, obesity and bariatric surgery at the Leicester Diabetes Centre in the United Kingdom. Herring and co-investigators undertook a systematic review and meta-analysis of studies involving adult weight-loss surgery patients. It included measures of pre- and postoperative physical activity and function. Their findings were published recently in Obesity Reviews.

“Physical activity and physical function research in those individuals undergoing or who have undergone bariatric surgery was and still is in its infancy,” Herring says. “Given that the literature in this research area is rapidly growing, a comprehensive and up-to-date review of the evidence was due. Early research was predominantly based on self-reported measures of both physical activity and physical function. More recent research has objectively measured these areas, hence the reason for including research looking at both objective and self-reported physical activity and physical function [in our review].”

Activity Takes a Step Up

Fifty studies met the researchers’ criteria for inclusion in the review, including 26 whose data made up the meta-analysis. Most patients in the studies had undergone Roux-en-Y gastric bypass or gastric banding.

“We found evidence demonstrating that objective and self-reported physical activity improved by 12 months after bariatric surgery,” Melanie J. Davies, CBE, MB, ChB, MD, FRCP, FRCGP, Co-director of the Diabetes Research Centre and Professor of Diabetes Medicine at the University of Leicester in the United Kingdom, stated in a news release. “A decrease in objectively measured moderate to vigorous activity and an increase in step count at three to six months indicated a shift towards a greater amount of lower intensity physical activity within the first six months after surgery. Walking, musculoskeletal and self-reported physical function all improved by 12 months.”

The data seemed to suggest that losing weight after bariatric surgery spurred patients to walk more.

“When looking at walking as a measurement of physical function, walking increased at a greater rate than physical activity or weight loss,” Herring says. “This may suggest walking improves as a result of weight loss, although physical activity is likely required for improvements to be maintained once the rate of weight loss slows or plateaus.”

The nature of the link between improved physical activity and function and weight loss after bariatric surgery remains unclear, but it may be related to the body’s inflammatory response to shedding pounds, according to Adolfo Z. Fernandez, MD, Associate Professor of Surgery at Wake Forest Baptist Health in North Carolina.

“There’s a decrease in inflammation and inflammatory markers that translates into less arthritis and joint pain,” Dr. Fernandez says. “Less pain translates into more activity, which we know helps with joint pain. Psychologically, [weight loss] improves the way patients see themselves. They always tell us their energy is better after the weight is off, like they’ve gotten a brand-new battery pack and have this new energy and want to get out and use it.”

Other researchers have noted improvements in physical function and joint pain following bariatric surgery. In a 2016 study in JAMA, a multi-institutional team of investigators led by researchers from the University of Pittsburgh found that about 58 percent of participants experienced less overall pain, 77 percent enjoyed better physical function, and 60 percent had improved walk times 12 months after weight-loss surgery. Approximately 75 percent of patients with severe knee or hip pain or disability saw improved knee pain and hip function. Rates of improvement in overall pain and physical function declined significantly between years one and three after surgery.

The Exercise Imperative

The next task for researchers is to understand more fully why patients are able to be more active after bariatric surgery and how to better use exercise to improve outcomes.

“Results from current exercise trials suggest the importance of structured exercise after bariatric surgery to optimize physical activity, physical function and fat mass loss, [as well as] preserve fat-free mass,” Herring says. “More exercise interventions are needed after surgery. The majority of current exercise interventions are initiated within the early postoperative stages. Physical activity interventions should also be utilized to optimize weight-loss outcomes associated with bariatric surgery and improve patients’ physical function and overall quality of life. Thus, more exercise interventions at the point of weight regain, typically experienced 12 to 24 months post-bariatric surgery, could be more beneficial and possibly incorporated into routine care.”