BOOK OF ABSTRACTS 30th Annual Congress of the EUROPEAN COLLEGE OF SPORT SCIENCE (1 - 4 July 2025)

Title: Effect of a 12-week lifestyle intervention program on free-living glycemic profile and cardiometabolic health in breast cancer survivors with metabolic syndrome. Abstract: Cancer treatments and a sedentary lifestyle increase the risk of type 2 diabetes (T2D) in breast cancer survivors (BCS). Lifestyle Interventions (LI), which provide physical activity (PA) and dietary guidance, may be an effective adjunctive treatment for BCS, but the impact of exercise training on glucose homeostasis remains inconclusive [1]. This study aimed to compare glucose variability indices between two groups of BCS participating in the MoviS clinical trial [2]. BCS patients with metabolic syndrome (n=27, 52.3±8.6 yrs [mean ± SD]) were randomized into a control group (CG, n=12) and an intervention group (IG, n=15). All patients received recommendations on PA and Mediterranean diet before beginning a 12-week trial, during which they kept a daily log for PA. IG patients also underwent a 3-time-a-week aerobic training program with progressive increases in exercise intensity (40-70% of heart rate reserve) and duration (20-60 min). Before (T0) and after (T1) the trial, participants’ body composition (BIA), cardiorespiratory fitness (GXT estimated VO2max), and cardiometabolic profile (routine laboratory parameters) were assessed along with glycemic variability (flash glucose monitor - FGM), which was assessed over 14 days (12±1.8 days) after T0 and before T1. Glycemic variability was calculated with the EasyGV software (v.9.0.R2). Statistical significance (α=0.05) was determined using a Repeated Measures GLM (SPSS software v.17). At T1, both groups significantly improved fat mass (CG -1.0%; IG -3.8%), triglycerides (CG -4.2% IG: -15.9%), insulin levels (CG -14.1%; IG -15.6%), and HOMA-IR (CG -13.7%; IG -16.3%). Cardiorespiratory fitness (GC +3.1%; IG +16.4%) and between-day glycemic variability index (CG +12.5%; IG -3.6%) significantly changed in both groups and resulted significantly better in the IG compared to the CG. Time spent within the normal glucose range (CG -11.0%; IG -1.8%) and with a glycemia above 180 mg/dL (CG: +1.1%; IG +0.7%) worsened at T1. Although time x group interactions were, respectively, nonsignificant and barely significant, CG changes were broader. The LI program improved body composition and cardiometabolic health in BCS patients at high risk for T2D, with an overall, although nonsignificant, lower effectiveness in CG than in IG patients. Since aerobic training effectively increased cardiorespiratory fitness solely in the IG and given that selected parameters of the glycemic profile improved significantly more in the IG than in the CG group, improvements seem to be attributable to the supervised exercise as an adjunctive effect over guidance alone. However, other glycemic parameters did not improve in IG patients. Thus, further research is needed to support the role of aerobic training in improving glycemic profile in BCS at high risk of diabetes.