The prevalence of knee osteoarthritis, a degenerative joint disease characterized by the degradation of articular cartilage, is correlated with the rise in obesity. The rising rates of obesity in children and adults highlight the need for identifying a sustainable physical activity that promotes fitness while mitigating initiation and progression of osteoarthritis. The objective of this study was to determine an effective rehabilitation and lifelong fitness sustainment exercise regimen that minimize risk of osteoarthritis in individuals with high body mass index (BMI). The aim was to examine knee medial and lateral contact forces in gait and cycling training. Gait at self-selected speeds and cycling at moderate resistance were studied using motion analysis in normal BMI and high BMI participants. Individuals with high BMI exhibited abnormal kinematics and increased kinetics in gait but neutral knee abduction-adduction angles, lower knee contact forces, and balanced mediolateral force distribution in cycling. The combination of maladaptive kinetics (excessive cartilage loading) and altered kinematics (primarily knee adduction angles) observed in gait for the high BMI cohort demonstrate the profound adverse effect of weight bearing and impact exercises on knee biomechanics. Exercise rehabilitation modalities should aim to minimize cartilage loading, correct altered knee angles, and prioritize balanced mediolateral force distributions in individuals with high BMI. Cycling, a non-weight bearing and low impact exercise, addresses all these factors because it constrains kinematic patterns with the pedals and carries significant body weight on the saddle.