# Women with metabolic syndrome show similar health benefits from high-intensity interval training than men PMID: 31821339 Journal: PloS one Published: 2019-12-10 Authors: Guio de Prada V, Ortega JF, Morales-Palomo F, Ramirez-Jimenez M, Moreno-Cabañas A, Mora-Rodriguez R ## Question Do women and men with metabolic syndrome differ in cardiorespiratory fitness, maximal fat oxidation, body composition, and metabolic syndrome component responses after 16 weeks of supervised high-intensity interval training? ## Summary This single-arm supervised cycling HIIT study followed 119 middle-aged adults with metabolic syndrome for 16 weeks to test whether women and men responded differently. The 43-minute sessions were performed 3 times per week and used 4 by 4-minute intervals at 90% peak heart rate with active recovery. Cardiorespiratory fitness, ventilatory-threshold measures, oxygen uptake efficiency slope, maximal fat oxidation, blood pressure, waist circumference, body weight, fat mass, and metabolic syndrome Z-score improved after training, with no meaningful sex difference in progression. No adverse events were reported, but the study lacked a non-exercise control group. ## Population - 119 Caucasian adults of European descent with metabolic syndrome; 63 women and 56 men. - Sample size: 119 - Age: 31-72 years; women 52.5 +/- 7.0 years and men 54.8 +/- 7.6 years. - Sex: 63 women, 56 men. - Fitness level: Deconditioned/metabolic syndrome adults; baseline VO2max was slightly below age- and sex-predicted normative values. - Health status: Metabolic syndrome, with exclusion of untreated cardiovascular, respiratory, or metabolic disease and exercise intolerance. ## Methodology - Prospective pre-post intervention analysis of the aerobic-training-only branch of a larger study, comparing changes over time between women and men. - 16 weeks. - Exercise Physiology Laboratory and University of Castilla-La Mancha campus training room in Toledo, Spain. ## Protocol - Supervised cycling HIIT. - Modality: Stationary cycling. - Work intervals: 4 minutes at 90% HRpeak. - Recovery: 3 minutes active recovery at 70% HRpeak. - Sets or repetitions: 4 intervals. - Intensity: 90% HRpeak for work intervals; 70% HRpeak for warm-up and recoveries. - Session duration: 43 minutes. - Frequency: 3 sessions per week. - Program length: 16 weeks. - Progression: No progression rule reported; intensity prescribed from individual HRpeak. - Sex-stratified same-protocol comparison. - Modality: Stationary cycling. - Work intervals: 4 minutes at 90% HRpeak. - Recovery: 3 minutes active recovery at 70% HRpeak. - Sets or repetitions: 4 intervals. - Intensity: Same relative heart-rate targets in women and men. - Session duration: 43 minutes. - Frequency: 3 sessions per week. - Program length: 16 weeks. - Progression: No progression rule reported. ## Outcomes ### VO2max Status: improved VO2max increased in women from 18.4 +/- 3.7 to 21.5 +/- 4.3 mL/kg/min and in men from 25.1 +/- 4.8 to 28.7 +/- 5.1 mL/kg/min, with no significant time by gender difference. Time p<0.001; time by gender p=0.280 for mL/kg/min. ### Cardiorespiratory fitness surrogate measures Status: improved VO2 at ventilatory threshold, OUES, and VE/VCO2 slope improved after training without sex-differential progression. VO2 at VT time p<0.001, time by gender p=0.184; OUES time p<0.001, time by gender p=0.915; VE/VCO2 slope time p<0.001, time by gender p=0.484. ### Maximal fat oxidation Status: improved MFO increased in absolute and fat-free-mass-normalized values similarly in women and men. Absolute MFO time p<0.001, time by gender p=0.095; normalized MFO time p<0.001, time by gender p=0.713. ### Metabolic syndrome components Status: mixed Blood pressure, waist circumference, and MetS Z-score improved, while triglycerides, HDL, and fasting glucose did not significantly change. SBP, DBP, waist circumference, and MetS Z-score time p<0.001; TG p=0.439, HDL p=0.845, fasting glucose p=0.698. ### Safety Status: no clear change No adverse events were reported during training or exercise testing. ## Practical Insights - A 4 by 4-minute cycling HIIT structure performed 3 times weekly can improve multiple fitness and cardiometabolic measures in supervised adults with metabolic syndrome. - For this heart-rate-prescribed protocol, women and men had similar relative adaptation despite baseline differences. - Body-weight reduction was more strongly associated with MetS Z-score improvement than CRF changes in both sexes. - Clinical translation depends on screening, heart-rate monitoring, and supervision. ## Limitations - No non-exercise control group. - No complete heart-rate records for every participant and session. - Possible unmeasured changes in habitual diet or daily physical activity. - No direct cardiac, pulmonary, or mitochondrial measurements. - Only participants meeting true VO2max criteria and attending at least 85% of sessions were included in post-training evaluation. ## Safety And Adherence - No adverse events were reported among volunteers during training or exercise testing. - Participants underwent medical screening and resting ECG before testing. - Exercise testing included ECG and blood-pressure monitoring. ## Original Sources - [PubMed](https://pubmed.ncbi.nlm.nih.gov/31821339/) (pubmed) - [DOI](https://doi.org/10.1371/journal.pone.0225893) (doi) - [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6903716/) (full text) ## Agent Guidance Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.