Compositions are described that include a betacryptoxanthin extract, rich in trans-betacryptoxanthin, which are prepared by a cost and time effective process and are for use in methods of enhancing cardio-respiratory fitness for physical performance and exercise endurance and to maintain healthy lung function. Betacryptoxanthin extract is prepared by a cost and time effective process of saponification and column chromatography, in which saponification cycle time, solvent amount, column separation time and silica amount are reduced, thus making it industrially viable. Betacryptoxanthin compositions increase exercise time, endurance performance, and lung capacity and maintain healthy lung and cardiovascular function during such physical activities. The compositions also improve physical performance, attenuate muscle fatigue, and enhance aerobic respiration utilization capacity. The compositions are safe for consumption, and can be employed for enhancing cardio-respiratory fitness when administered in an effective amount.