The phrase "oxygen levels in the blood" refers to the amount of oxygen present in our blood. It is an important measure as our body needs oxygen to function properly, and low oxygen levels in the blood can be a sign of health issues. Full definition
Not only is it one of the cheapest fitness activities around but including jump rope in your weekly winter workout routine will greatly increase oxygen levels in the blood. (fitbodyhq.com)
During this time, researchers reported that oxygen levels in the blood remained normal. (seeker.com)
When oxygen levels in the blood drop, your body responds by releasing stress hormones and partially waking you up ---- as many as 400 times a night. (webmd.com)