The germ masks does not restrict airflow to the athlete. It keeps the germs from being spread by the user.
Training Mask is a tool to help athletes take their workouts and training to the next level. By conditioning your lungs and creating pulmonary resistance, your diaphragm is strengthened, thereby making your lungs work harder. When lungs work harder, the surface area and elasticity in the alveoli is increased, thus increasing your stamina and ability to go harder at your sport. Like any other tool, this doesn’t replace hard work and training. It helps the athlete create resistance and will continue to push their body.
I’ve been using the mask for 6 months and have seen dramatic improvements in my run and bike splits. Physically I don’t get as fatigue when I’m pushing my max and mentally, it has given me a huge confidence booster.