Introduction: Knee osteoarthritis (kOA) is a chronic degenerativedisorder. Aerobic exercise programs have been effectivetreatments to reduce symptoms in kOA. However, studiescomparing land- and water-based interventions did notcontrol for the intensity of exercise programs. Objectives:Investigate the effects of walking programs with a controlledprogressive workload in water compared to land in terms ofpain, functional and physical performance, and quality oflife in elderly women with kOA. Materials and Methods: Thewalking training programs were divided into two groups:1) land-based aerobic training (LB); and 2) water-based aerobictraining (WB). Each training session was divided intothree phases: 1 – Warm-up (5 minutes): stretching exercises;2 - Training (30 to 55 minutes): walking at target heart rate;3 – Cool-down (5 minutes). Sixteen elderly women with kOAunderwent assessments of functional performance using thesix-minute walk test (6MWT) and the stair test (ST), whilephysical performance, maximum oxygen consumption (VO-2max) and anaerobic threshold (AT) were determined during aprogressive test. kOA was assessed by the Western Ontario andMcMaster Universities Osteoarthritis Index (WOMAC), andquality of life was assessed using the Medical Outcomes Study36-Item Short Form Health Survey (SF-36). All parameters werereevaluated after 12 weeks of aerobic training that consisted ofwalking (duration: 30-55 min.; intensity: 72-82% of maximalheart rate). Results: No significant difference between the LBand WB groups was found. There was a reduction in self-reportedpain (by WOMAC), increased performance in the 6MWTand ST, increased VO2max and VO2max corresponding to ATand improved quality of life (by SF-36) in both groups aftertraining compared with before intervention. Conclusion:Land-based aerobic training was as effective as its water-basedequivalent in clinical, physical and functional parameters inelderly women with knee OA.Keywords: Osteoarthritis of knee; Elderly; Aerobic training.