Every golfer wants to hit the ball farther.

“There’s a common misconception that hitting…harder will result in a longer shot,” says Joey Diovisalvi, founder of Joey D Golf Sports Training Center in Jupiter, Fla. “You want to swing faster, not harder.” In general, he says, if you have good speed when the club head makes contact with the ball, it creates a more aggressive trajectory. The golf swing is an explosive movement, he says, “but you want to create controlled speed—not chaotic speed—and that takes strength, flexibility and mobility and balance.”

Mr. Diovisalvi says club-head speed begins with building a strong, stable foundation in the legs and core. It also requires a full range of motion through the hips and spine. Golfers coil their bodies during the backswing to follow through after the point of impact. If you don’t have the mobility in your mid-back and hips to bring the club fully back, you are cheating your swing, he says.

Mr. Diovisalvi has worked with golf greats including Dustin Johnson, Brooks Koepka and Vijay Singh. He notes that Mr. Johnson makes speed training a key part of his workouts. “For the past 10 years, Dustin has used swing sticks of different weights and will swing 10 times to the right and 10 times to the left, and might do 60 swings,” he says. “He’s building strength to build speed, and at the same time the repetition creates muscle memory.”

He sprinkles these exercises into a dynamic warm up for his athletes, but says they can be strung together for a single workout as well. “Less is more to start,” he emphasizes. “As soon as you start to feel your form fall apart, bring the speed down to a point where you can maintain control and proper form.”