Many breast cancer survivors (BCS) continue to face lasting side effects, among which breast cancer–related lymphedema (BCRL) is especially frequent. Exercise is generally recognized as a safe approach to support recovery and enhance daily functioning in BCS, either living with or susceptible to BCRL. Yet, the influence of combined aerobic and resistance (concurrent) training in this group is not well established. This investigation assessed the impact of a 12-week guided concurrent exercise regimen followed by another 12-week period without training on molecular, physical, and clinical indicators in BCS. Eleven participants with or at risk for BCRL completed a single-group study assessing changes after the 12-week program and again after the follow-up period. The parameters examined included molecular (92 inflammation-associated proteins), functional (upper- and lower-body strength, grip force, and aerobic capacity), and clinical measures (body mass index, arm size, tissue and muscle thickness, joint range of motion, habitual activity, heart rate variability, pain, and quality of life [QoL]). Following the exercise intervention, upper-body and grip strength, pain perception, emotional state, and overall QoL improved significantly. At the end of the follow-up, the gain in rowing strength persisted, and several inflammatory proteins declined notably. Twelve weeks of concurrent training enhanced muscular strength, reduced pain, and improved QoL in BCS without provoking inflammation. During the follow-up, strength benefits were maintained and inflammatory protein levels fell, emphasizing the promise of this training type. Broader and controlled research is warranted to confirm these findings.
