Are you ready for this? The best training for golf: swinging a golf club. And the principle applies to any sport or activity. The best way to train for the 100-Yard Dash is to practice the dash. Although it may seem obvious, there is actually a technical term for this. It’s called Specific Adaptations for Implied Demand, or the SAID principle.
So what makes playing more golf, or practicing any skill more, the best workout? Repetition of the movement creates the muscle firing pattern retention (i.e., muscle memory) needed for improvement. Augment it with physical training to increase speed, stability and mobility for the golf swing motion.
A proper strength training program for golf should start with a needs-based analysis. You must first decide what goals you want to accomplish through your training. Next, determine your strengths and weaknesses with a self-analysis, asking yourself questions like: What is my major area of focus or area of weakness? How does it relate to the demands of the sport? What is my major concern about sustaining an injury? Finally, make a daily, weekly and yearly plan of action.
Your golf training program should focus on stabilizing the following three areas.

Abdominal and Lower Back

Abdominal and low back training is often referred to as core training. Many people define the core as comprising the muscles from the chest to just above the knees. However, for this golf program, we focus only on the abdominal area. The abdominal region connects the lower and upper body. Strong abdominal and low back muscles allow you to execute the proper motion when swinging a club. Stable abs facilitate the change of direction from the backswing to the forward swing. To make the best impact on the golf ball, you also need to keep a proper spine angle during the swing.
The best way to train the abdominals is to do as many activities as you can in the golf stance. Here are two examples:
Standing Plate Front Raise Part 1, Part 2
Standing One-Arm Cable Row Part 1, Part 2

Hips

The hip region plays an integral role in the rotational movement of the golf swing. During the swing, there is both an internal and external rotation of the leg bone. The muscle connections in the hips need to allow these movements, so hip mobility is critical during the swing. Improving the strength of the gluteus muscles also helps with weight transfer during the golf swing. The gluteus muscles promote stability during the back swing and forward swing. Here are two exercises that focus on activation of the gluteus muscles.
SL Quarter-Squat Part 1, Part 2
Back Lateral Tube Walks Part 1, Part 2

Scapulae 

A stable scapulae region makes sure the torso is turning properly during the swing. Scapulae stability also helps reduce excessive arm movement. Strengthening the shoulder blade regions also helps overall posture. Stability in the shoulder blades allows the arms to “stay connected” during the golf swing. Here are two exercises for scapulae stability.
Prone T Raise Part 1, Part 2
Scapular Wall Slides Part 1, Part 2
Stability training of the abdominals, hips and scapulae helps build a solid foundation for improving your swing’s efficiency and consistency. As you continue to swing the club, fatigue increases and the weaker muscles begin to limit  activity, enabling the stronger muscles to control the movement. The abdominals, hips and scapulae are usually the weaker muscles, so strengthening them helps ensure proper body position throughout the golf swing.