When I joined the gym, I got some "gym bucks" that you can choose to spend on a variety of activities. I chose to use all of mine for some sessions with a personal trainer. And she's kicking my butt! (in a good way)
She's a triathlete, too, and has already given me suggestions on how to improve my time. (My goal each year is just to beat my previous time, and so far, each year I've done that.) I also told her I wanted to tone up in general. And I may have mentioned I don't like my upper arms...hence the incredible arm workouts she has added to the cardio and strength training.
Most days, some muscle group feels a bit sore. But overall, I feel so much stronger, have more energy and am sleeping like a rock. It's great!
My gym workouts are also supplemented by my sister's Bollywood aerobic class on Sunday nights, too. I'm feeling stronger (and more confident with the steps) there, too, and it's fun!