CUT YOUR WORKOUT TIME IN HALF - Training Mask by SPARTHOS makes workouts more effective by simulating high altitude. It will force you to take full and deeper breaths, toughening your diaphragm and respiratory system. UNLOCK THE CHAMPION IN YOU Breathe efficiently and reach unmatched endurance. Less fatigue, hardened body, more energy after training. PROVEN RESULTS, PROVEN TECHNOLOGY - SPARTHOS Workout Mask is anatomically designed, cutting edge technology to energize any sport - cardio, gym, running, cycling or aerobic exercises. Simulate altitude training and exercise your breathing anywhere. AMPLIFY THE INTENSITY 16( ) breathing levels at your disposal - from beginner to pro. Change air flow intensity during workouts. No need to take your mask off