Lifting Weights Shown To Reverse Effects Of Osteoporosis In Heart Transplant Patients

June 18, 1996

Physicians have long known that performing aerobic exercise helps patients with transplanted hearts pump blood better.

Now researchers say pumping iron may be just as critical to the overall health of these patients.

Ask heart transplant patient Robert Lewis about the benefits. He travels 200 miles round-trip to work out one day each week at a special gym on the University of Florida campus.

“I have no limit to the walking I can do now, whereas I was very limited before. I can do medium-type work around the house: lifting some furniture, working in the garden, helping my wife clean,” Lewis said.

The 61-year-old Eustis resident, who underwent a heart transplant at Shands Hospital at UF two and a half years ago, participates in a weight-lifting program designed to prevent osteoporosis, which commonly occurs as a side effect of the medication taken to prevent rejection of the transplanted organ.

Almost 100 percent of the people who undergo heart transplants develop osteopenia, or weakening of the bones, and one half of these people will develop osteoporosis, a disease that can cause spontaneous fractures.

UF researchers have found weight lifting may be a simple solution to this potentially back-breaking problem.

“We went back to something very basic,” said Randy Braith, an exercise physiologist with UF’s Center for Exercise Science in the College of Health and Human Performance. “It’s well-known that people who engage in weight-lifting exercises have very thick, strong bones. We measured bone mineral density in heart transplant patients and began a program of weight lifting after surgery to see what effect, if any, exercising might have on strengthening bones.”

What they discovered was surprising. Bone mineral density measurements performed after surgery on heart transplant patients from Shands showed a loss in bone mineral density of up to 25 percent during the first two months.

However, transplant patients who began strength training two months after the transplant surgery were able to restore and maintain bone mineral density to the same level it was prior to the operation, he said.

“Resistance training should become part of any post-operative reconditioning rehabilitation program for heart transplant patients,” Braith said.

“Traditionally, cardiovascular exercises have been prescribed to recondition heart muscles, but this type of exercise does not make an impact on osteoporosis.”

Other approaches, such as taking calcium supplements and hormone replacement therapy, have been tried to no avail in attempts to offset this debilitating problem. “The anti-rejection drug always seems to win in this situation,” Braith said.

The medication is necessary for all transplant patients to take to prevent rejection of a donated organ.

“Three medications are given to transplant patients to prevent rejection: Cyclosporin, Azathoprin and prednisone. The side effect of prednisone is a thinning of the bone, or wasting,” Braith said.

Braith and cardiologist Dr. Roger Mills with UF’s College of Medicine enlisted 16 transplant patients from Shands for the study. Bone mineral density measurements were taken at the onset of the study, at three months and again at six months.

Researchers split participants into two groups: a control group that performed only cardiovascular exercises and another group that combined cardiovascular exercises with weight training three times a week.

In the weight-training program, participants performed one set (10 to 15 repetitions) of exercises using a machine that isolates the lower back, a region of particular concern since the bones demineralize quickly and, therefore, fracture easily.

Participants also used eight different upper and lower body exercise machines. “Our objective was to stimulate the entire skeleton to grow and remineralize,” Braith said.

Another goal was to return people who have had a heart transplant to jobs and functional living again.

“A good rehabilitation strength-building program can counterbalance the effects of prednisone substantially,” Mills said. “Patients can go back to work and not fear having fractures, which can affect a person’s ability to sit, stand and bend.”