What Are Some Exercises I Can Do To Get Back Into Shape For Horseback Riding?

Buy an large exercise ball to sit on in front of your computer, instead of your usual chair. You can use the roundness of the ball to stabilize your core, especially your sit bones. You can straddle the ball to stretch your inner thighs, and do squats to improve your ankle strength. It pulls on your lower back, sitting on one, and that makes for a less stressful ride. Any exercise you choose should be one that you enjoy doing, and if it hurts, STOP.

Barn work usually keeps you in great shape. What kind of riding are you planning on doing? The best exercises to do are core strengtheners - crunches, planks, work with a balance ball. These all strengthen your back and stomach muscles. You don't need hugely strong arms, unless you're riding tough horses who will be trying to get there heads down to buck, or you're galloping race horses. And it sounds like you're a western rider, so probably don't post when you ride. And even if you do, it doesn't require strong legs, as the horse should be tossing you up and forward as you post. You should do some cardio if you plan to be doing a lot of cantering and trotting - either do running or jumping rope. For arm strength, just use free weights or resistance bands. As for how long - - plan on at least 3x week. Start off doing as many reps (usually about 8) as you can, take a break and repeat for a total of 3 sets each exercise. You really have to listen to your own body to determine exactly how many/how long, etc, as we have no idea where you are physically. But 3x per week, minimum is necessary to see any cv or strength improvement. (And, YES, yoga and pilates are GREAT for riders)