Lifting Weights, Easing Swelling: Trial Puts Resistance Exercise to the Test Against Breast Cancer Lymphedema

For the millions of women who survive breast cancer each year, one of the most stubborn and distressing legacies of treatment is not the tumor itself but the swelling that can follow it. Breast cancer-related lymphedema, a chronic accumulation of protein-rich fluid in the arm, affects roughly one in five patients worldwide, and retrospective surveys of Chinese patients suggest the figure there may be even higher, at around 25 percent. Now, a randomized controlled trial conducted at Tianjin Medical University Cancer Institute and Hospital has added fresh, carefully measured evidence to a question that has divided rehabilitation specialists for years: can supervised resistance training, combined with compression garments, actually shrink the swollen limb rather than merely keep it from getting worse?

The study, published in Holistic Integrative Oncology, enrolled 108 women between November 2022 and June 2023, of whom 98 completed the protocol, with 49 assigned to each arm. To be eligible, patients had to be between 18 and 65 years old, have unilateral upper-extremity lymphedema defined as a circumference difference of at least two centimeters between the affected and healthy limbs, and have finished adjuvant chemotherapy and radiotherapy. Those with serious cardiopulmonary, orthopedic, neurologic, cognitive, or emotional disorders, metastatic cancer, or active infection were excluded. Randomization was performed by a blinded researcher using computer-generated numbers, with allocation concealed in sealed, sequentially numbered opaque envelopes, and all outcome assessments were carried out by an assessor who did not know which group each patient belonged to.

The intervention itself was a graduated, eight-week program delivered twice a day, five days a week, in small supervised groups of five to six women. Each session lasted roughly twenty minutes, split evenly between aerobic-style mobility work and resistance exercise using adjustable dumbbells. The resistance component included seated rows, latissimus dorsi pulldowns, one-arm bent-over rows, biceps curls, bench presses, and triceps extensions, performed in two to three sets of eight to twelve repetitions. Crucially, the load was individualized: each participant underwent a one-repetition maximum test before starting, then trained at just 20 percent of that maximum for the first two weeks, rising to 60 percent in weeks five and six and 80 percent in the final fortnight, with the absolute weight capped at 2.5 kilograms. Throughout, participants kept compression bandages on, in line with guideline recommendations that compression be worn during moderate resistance exercise at home.

The control group received standard complex decongestive physiotherapy, the internationally recognized gold standard that combines manual lymphatic drainage, compression therapy, skin care, and functional exercise. In the first month, these patients attended hospital-based sessions once a day, five days a week; in the second month, they self-managed at home with twenty minutes of aerobic exercise twice daily. What they did not receive was the progressive resistance component, allowing the trial to isolate the added value of weight training on top of conventional care. Adherence was tracked through electronic logs completed by physiotherapists, with high adherence defined as attending at least 80 percent of offered sessions, and participants reported their exercise through an internet follow-up platform with online access to therapists.

The primary outcome was limb circumference, measured at standardized anatomical landmarks: the midpoint of the ulnar styloid process, points 10, 20, 30, and 40 centimeters above it, and the axillary root. After eight weeks, the mean difference in circumference between the healthy and affected sides fell significantly in the intervention group, while the control group showed no significant change. The effect was most pronounced at the 10-centimeter and 20-centimeter marks above the elbow crease, where the between-group differences reached statistical significance. Upper limb function, assessed with the Disabilities of the Arm, Shoulder and Hand questionnaire and digital goniometer measurements of shoulder range of motion, did not differ significantly between the groups, a result the authors attribute at least in part to the modest sample size.

Perhaps the most intriguing finding concerned the mind rather than the muscle. Baseline anxiety, measured with the seven-item Generalized Anxiety Disorder scale, was comparable between groups, but after two months the intervention group’s anxiety scores were significantly lower than those of the controls. Depression, measured with the nine-item Patient Health Questionnaire, and quality of life, measured with the 36-item Functional Assessment of Cancer Therapy-Breast instrument, showed no statistically significant differences, although quality-of-life scores trended slightly higher in the exercising group. The authors suggest the absence of significance on those secondary measures may reflect the short eight-week window, which may simply have been too brief for broader psychosocial benefits to register on validated scales.

The physiological rationale for why lifting light weights could drain a swollen arm rests on what the researchers describe as a dual pump mechanism. Lymphatic vessels normally move fluid through their own rhythmic, autonomic contractions, but in lymphedema, valve insufficiency and damage to the muscular wall of the lymphatics impair this intrinsic transport, leaving skeletal muscle contraction as the dominant force pushing lymph back toward the torso. Breast cancer surgery damages chest wall and upper limb muscles, and scar tissue contracture can stiffen the shoulder, weakening this so-called muscle pump. Resistance training rebuilds that pump, while the flexion and extension of the joints themselves stimulates lymph nodes and vessels in what the authors call a joint pump, together promoting lymphatic return and reducing fluid accumulation. Compression garments worn during exercise provide the external pressure gradient that keeps newly mobilized fluid from pooling again distally.

The anxiety finding has a plausible neuroendocrine explanation as well. Anxiety is thought to arise, at least in part, from dysregulation of the hypothalamic-pituitary-adrenal axis, the body’s central stress system, producing hypervigilance and sympathetic overdrive. Resistance exercise acutely elevates testosterone and cortisol concentrations and, over weeks of training, appears to modulate this axis, offering a mechanistic bridge between mechanical work in the gym and measurable relief of psychological distress. The authors note that prior trials, including one in breast cancer patients receiving chemotherapy, failed to detect an anxiolytic effect of resistance training, and they caution that differences in populations and assessment tools mean the psychological benefits in lymphedema patients still require confirmation in larger studies.

The trial’s authors are candid about its limitations. The sample was small, the follow-up was short, and the study was conducted at a single center, all of which constrain the generalizability of the results and may explain why functional status and quality of life did not reach significance. Missing data were excluded from analysis, and the statistical thresholds were conventional, with significance set at P less than 0.05. Still, the direction of the findings aligns with a growing body of evidence: systematic reviews and meta-analyses have concluded that resistance exercise is safe for lymphedema patients, improves muscle strength and physical function, and does not trigger or worsen the condition, overturning decades of advice that told survivors to baby their affected arms.

The broader implications extend beyond swelling. Epidemiological research has linked resistance training at least once a week to a 33 percent reduction in mortality risk among breast cancer survivors, and earlier work by members of this research community showed that a twice-weekly, slowly progressive weight training program halved the incidence of clinical events requiring medical care for lymphedema, even if it did not reduce arm swelling itself. What the Tianjin trial adds is the suggestion that, when paired with compression, supervised progressive loading may actually reverse some of the circumference difference that defines the disease. For a condition long considered incurable and managed mainly through meticulous maintenance, the message to survivors is quietly radical: the affected arm is not fragile, and carefully dosed strength training, done under professional supervision with proper compression, may be one of the most effective tools available for taking back both the limb and the peace of mind that cancer treatment so often takes away.

Subject of Research: Resistance exercise and compression garment therapy for breast cancer-related lymphedema

Article Title: Effects of resistance exercise and compression garments in the management of breast cancer-related lymphedema: a randomized controlled trial

Article References: Zhu, M., Li, M., Li, J., Wu, P., Qiang, W., & Wang, Y. (2026). Effects of resistance exercise and compression garments in the management of breast cancer-related lymphedema: a randomized controlled trial. Holistic Integrative Oncology, 5(1), Article 25. https://doi.org/10.1007/s44178-026-00231-6

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00231-6

Keywords: breast cancer, lymphedema, resistance exercise, compression garments, randomized controlled trial, cancer rehabilitation, arm circumference, anxiety, quality of life, complex decongestive therapy, cancer survivorship, exercise oncology