Just as a small PSA… If you are training in your basement, you should try to check your radon levels. I have heard that the radioactive particles carry a static charge, so using a fan should keep them out of the air you are immediately breathing but it would really suck to eventually give yourself lung cancer while trying to live a healthier lifestyle.
We had slightly elevated levels of radon in our basement, around the level of “keep monitoring” but have heard that some people in our neighborhood have had twice that level when they had their test performed. So we decided to get an active radon fan for the foundation. The most recent test for our workout room is now coming back undetected. Considering all of the money we pay for equipment, the mitigation system was pretty cheap! I’m not sure how bad radon is outside of the US, but it is quite common here.