The Truth About Weight Loss Drugs and Exercise (It’s More Than Just Weight Loss)

A recent study indicates that exercise may mitigate the adverse effect of fast weight reduction on bone density in those using weight-management medications.

The study’s focus was ligandude, a GLP-1 receptor agonist used to treat type 2 diabetes and encourage weight loss. The journal JAMA Network Open published it. Researchers found that those who used the medication but didn’t exercise often saw a loss in bone mineral density. In contrast, individuals taking the medicine and engaging in regular exercise saw no loss of bone mass Even if they lost more weight.^[1]

Although the emphasis of this study was only on liraglutide, senior author Signe Sørensen Torekov, PhD, stated that she “would presume” that exercise would also prevent bone loss in those using other GLP-1s, such semaglutide, which is the main component of the well-known weight-loss medications Wegovy and Ozempic.The Department of Biomedical Sciences at the University of Copenhagen’s Professor Torekov said, “It follows the same mode of action…but it has to be investigated.”

Combining these drugs with exercise had “not been investigated in the context of bone health” until this study, the researcher noted.

Measuring Weight and Bone Loss

In order to conduct the study, the researchers “secondarily Examined” a randomized clinical trial that was carried out at the University of Copenhagen and Hvidovre Hospital in Denmark between August 2016 and November 2019. 195 obese but non diabetes participants between the ages of 18 and 65 participated in the experiment. With an average age of 42.84, over two thirds of them were female.

After following a diet of around 800 calories per day for eight weeks, the volunteers were randomly divided into four groups.One group received daily treatment with three milligrammes (mg) of liraglutide for nearly four years. Another group was given a placebo. A third group had moderate and vigorous activity whereas a fourth group took the drug and exercised.

The exercise program consisted of group sessions of 30-minute indoor cycling intervals followed by 15-five minutes of circuit training including strength-based (Resistance) exercises and aerobic conditioning.

According to Torekov, “individual circuit training, brisk walking, cycling, and running were the most often performed exercises.” “To track adherence, participants wore heart rate monitors during every workout.”

The researchers found that the liraglutide-taking group lost more bone than the exercise group, even though both groups lost the same amount of weight. The group that combined exercise and GLP-1 lost the greatest weight, but their bone mineral density values did not change from those of the non-medication group. In addition, individuals on liraglutide lost weight in a manner comparable to the combined group, but they lost more bone mineral density in their spine and hips than in the case of those who only exercised.

Because of research limitations including “no BMD assessments, short duration of intervention, or the use of other diabetic drugs that may have affected fracture risk,” Torekov clarified, it is unclear if weight management drugs cause a decrease in bone density.

Vijaya Surampudi, MD, MS, a quality improvement officer for UCLA Health and associate professor of medicine at the David Geffen School of Medicine at UCLA, highlighted that this study is especially “unique” in that it concentrates on those who are fat yet do not have diabetes.  This distinction makes it clearer that any bone loss observed is likely due to the medication itself, rather than being linked to diabetes, which often complicates such findings.

Additionally, she said, “This study gives us more information on whether lifestyle measures can reduce the decrease in bone mineral density with weight loss.”

Exercising for a ‘Better’ Outcome

A few things should be taken into account, even if the study indicates that exercise might improve the bone health of those using GLP-1s.

For starters, the study’s target population was persons under 65 and those without long-term medical conditions like diabetes, thus these populations could not benefit from the findings.

Additionally, it only examined liraglutide, one GLP-1. Although experts agreed with Torekov that the results would probably hold true for other GLP-1s, Jane Howard, MB BChir, PhD, associate professor at King’s College, speculated that the beneficial benefits of exercise would not be as strong for users of these other medications. 

According to Howard, it’s likely that other GLP-1 receptor agonists could have similar effects. However, he notes that semaglutide, which leads to more significant weight loss, may pose a greater risk to bone health. The larger weight loss could result in a greater reduction in lean muscle mass, which may put additional physical stress on bones and outweigh any potential benefits to bone density.

Nevertheless, it seems reasonable that exercise might support maintaining bone health in GLP-1 users, according to experts. Muscle mass is increased and maintained by exercise, “which affects the biomechanical stress and force on bones during movement,” according to Howard.

In order to preserve muscle mass and bone, it is recommended to undertake “weight-bearing exercises” such as running, walking, and resistance training. In contrast, swimming, including weight-bearing exercises, is good for strengthening the heart but, as the speaker explained, does not seem to be effective in preserving long bone density.

According to Surampudi, there are several aspects to maintaining bone density, weight loss, and general wellness.

“Diet and exercise are fundamental to healthy living and improving metabolic health,” stated Surampudi, “which is the big takeaway from this study.” “All studies continue to show that weight reduction therapies with drugs or surgery have superior outcomes when food and exercise are integrated, regardless of the endpoint—weight loss or metabolic health.”