You seem like a reasonably friendly guy. Surely you know someone who will come down and take pictures for you for free (or maybe a beer or a pizza or something like that).
As I understand it, you're looking for decent shots for your website. All you need is a buddy with one working eyeball and one working hand and any point and shoot camera sold within the last 10 years will have some kind of "sport" mode, which will reduce the shutter speed and allow you to take a picture of something that is moving without it looking like a picture of the Flash.
I know, this is an old post, but...
You need a fast shutter speed. Slow shutter speed gives the blur (intentionally or unintentionally).
The problem with poor lighting is you need to get creative with the settings. Lower amount of light would need things that you'd have to trade off to get the right balance...
Slower shutter speed = more light coming in. But it can get blurry easily, especially in stuff at MA pace. I'd go with 1/125 sec shutter speed and bump up and down as needed.
Aperature - how much the lens iris opens. The wider it opens (the lower the f/ number), the more light comes in. The trade off is shallower depth of field. Meaning less stuff will be in focus.
ISO - light sensitivity. Higher ISO will be brighter. Trade off is higher ISO = more noise (grain) in the picture.
You can use flash. But it should be diffused and/or bounced. Direct flash from a camera gives that bleached skin tone and/or deer in headlights look. If you sit for portraits at a studio, they usually us soft lights with umbrellas over them in multiple directions as flash to avoid this.
Sorry, it's just a stupid hobby of mine. And shooting events indoors in poor lighting is usually the bane of every photographer's existence.
Just thought of this now - how about shooting an outdoor workout? Not sure if you're near the beach for a beach workout. Our dojo (and organization) does an annual beach workout. It's followed by a BBQ with family and friends invited. Ask a few people to take pics. Even if you don't get any good pics, you'll still have a great time.