The effects of cooking temperature (50-90 °C) and time (10-120 min) on Warner-Bratzler (WB) tenderness measurement of longissimus lumborum (LL) muscle in 70-day-old rabbits were investigated. Cooking losses, total collagen content and collagen solubility of LL muscle were measured in parallel. Increasing cooking temperature caused a four-phase effect on WB measurement. Stress and total energy were significantly increased between raw meat and cooked meat at 50 °C, then they dramatically decreased to a minimum observed at 60-65 °C, and increased again to reach a maximum at 80-90 °C. Cooking losses exhibited an 83% increase between 50 and 80 °C. At 80 °C, stress and total energy values remained constant after 20 and 40 min respectively. LL muscle collagen content was 16.4±2.3 mg/g of dried muscle. Collagen solubility at 77 °C for 1 h was high: 75.3±8.1%.