Low Effort, High Performance, Jump Horse Rider Kettle Bell Figure 8 Squat Swings. Back Strengthening 

Effort Level 4. Helps to strengthen the horse rider's back, gluteal, quadriceps and hamstring muscle groups. Trains coordination. Stretches the hip, knee and ankle joints.
Formulated for equestrians but others will find it an effective core stability strengthening technique.
From the book by Caroline Lindsay - The Art & Science of Developing Postural Control for Horse Riding available on Amazon or if unavailable in your country, contact me directly at horsesaddlerider.com
Video demonstrations accessed by QR codes throughout the book.
HorseSaddleRider.com