According to U.S. Olympic Equestrian Steffen Peters, who shared his personal training routine in "Dressage Today," strong lower abs are important for keeping your pelvis in correct alignment while riding. Your lower abs balance your weight on your seat bones so you can maintain the most effective posture during your ride. Exercises that strengthen your entire core and engage the lower abs are particularly beneficial for an equestrian.
Create a plan or schedule to do ab exercises each week, in addition to your regular riding schedule. According to the American Council on Exercise, you need to do at least two strength-training sessions per week to see results. However, make sure you give your muscles at least 48 hours to recover between workouts to avoid over-training and injury.
Do full-body curls to strengthen your upper, middle and lower abs in one exercise. Lie on a mat with your knees bent and feet on the floor. Place your hands behind your head like you're going to do a crunch. Lift your head and shoulders from the floor as you lift your knees towards your chest. Slowly lower your feet and shoulders back onto the mat. Work up to 30 reps in one set.
Do bicycle crunches for your obliques and lower abs. Begin on the mat, lying on your back with your hands behind your head and your knees tucked into your chest. Straighten one leg. Lift your head and shoulders off the mat and twist as much as possible to touch your elbow to your opposite knee. Switch sides to complete one rep. Aim to do at least 20 reps per set. The lower you hold your straight leg, the more intense the exercise.
Include the v-sit exercise in your ab training program, since it's great for improving your balance and control on your horse. Lie flat on your mat and lift your legs off the floor at a 45 degree angle. Lift your shoulders off the floor and reach your arms out straight in front of you, holding them parallel with the floor. Pulse your arms up and down quickly for 30 reps. When you get stronger, try to balance in a more difficult variation of this pose. Reach your arms up straight above your shoulders, keeping your elbows close to your ears, and hold your body in a perfect "V" with your spine in straight alignment for as long as possible.
Improve your core strength and balance by sitting up tall on a stability ball instead of sitting in a regular chair. Keep one in your office and sit on it while you work at the computer, or keep one in your living room to sit on while you watch television. Balancing on a stability ball while keeping your spine straight, with each vertebrae stacked right on top of each other, uses the core muscles that help you stay balanced and in control when you're riding. Don't inflate the ball completely; leave it a little deflated for more of a stability challenge.