PURPOSE: The present case study examined the potential use of the AlterG Anti-Gravity Treadmill as treatment modality for extreme obese individuals. The special effect of the treadmill reduces ground reaction forces during walking through the use of lower body positive pressure. METHODS: One extremely obese (BMI 69.2) Caucasian 44 year-old female utilized the AlterG Anti-Gravity Treadmill during a 14 wk walking program to pilot test the protocol. RESULTS: At the conclusion of the study, exercise tolerance time increased 3-fold (initially 20 min increased to 65 min) while caloric expenditure increased 4-fold (initially 91.0 kcal/session increased to 442.7 kcal/session) without an increase in heart rate or perceived pain in her lower extremities. The participant demonstrated a 2.75% weight reduction, a decrease in upper body circumference measurements and lower extremity swelling of her knees and ankles, and a 9.7% decrease in fasting blood glucose (102mg/dL). CONCLUSION: Overall, the AlterG Treadmill enabled the participant to exercise and walk pain-free at a distance, intensity level, and speed that she could not accomplish while walking on her own and suggests that further study of this modality is warranted.