Dr. Tom Lawton is an ICU doctor in the UK who has spent time treating COVID patients. He wanted to disprove online claims that wearing a mask drops your oxygen levels, and reassure people that wearing a mask to go indoors is perfectly safe.
So he ran 22 miles WITH A MASK ON, and checked his oxygen levels every 20-30 minutes. (Watch his video below)
According to FOX 13, Dr. Lawton said:
Wearing a mask the whole time, oxygen saturations are normal if they’re over 95% and mine were at 98% every single time I checked.