What can be done for stroke prevention for someone who is having tias but is very active outdoors?

Stroke Prevention: You can help prevent a stroke if you control risk factors and treat medical conditions that can lead to a stroke. Some of the common risk factors for stroke: smoking, high blood pressure, high cholesterol, diabetes, obesity, inactivity, excess alcohol can all be treated. If your doctor recommends you take Aspirin or a blood thinner, take it. This can help prevent having a stroke.

TIA: Not enough information to even begin... First things first: overweight? High blood pressure? Smoking? High cholesterol? Yourself? Active outdoors doesn't help... If you have high blood pressure and be "active" may actually endanger you (if you have high blood pressure it goes up even higher during exercise).

Watch out for PFO's: The mainstay of Primary Stroke Prevention is modifying risk factors specifically blood pressure, cholesterol and blood sugar (if elevated) and making lifestyle change; sensible food choices, regular exercise, modest alcohol, and of course to stop smoking. In younger people Patent Foramen Ovale (PFO) is a rare but important cause of ischaemic stroke. Check with your Dr and consider Echocardiogram.