In 2018, Fabrício E. Rossi and a team studied 30 adults randomly assigned to three groups: back squat only, leg press only, or both, for 10 weeks of twice-weekly lower body workouts. Each group did 6 sets of 8-12 reps with 90-120 seconds rest, keeping other training the same. They measured max squat strength, body composition, jump height, and balance.