Step 2 - Exercise Selection
Plain and simple, a resistance training program should be structured around the muscular needs of the individual for sport performance or goal-oriented needs. Creating a program based on proper rep ranges and intensity loads is crucial to help the individual meet their goals.
There are literally hundreds, if not thousands of resistance training exercises, all of which can be split into 2 main categories, "Core Exercises" and "Assistance Exercises". Usually, when one thinks of "Core" exercises, we think of those that directly involve the abdominals or midsection. That is not the main reason why the name is derived for the "Core Exercises" I will detail below, but the midsection definitely plays a large part in these moves.
Core exercises are actions that involve large muscle areas (chest, shoulder, back, hip, thigh), involve two or more primary joints, and receive priority when an individual is selecting exercises as these are generally directly related to sport-specific applications. An example of a core exercise would be the bench press as it involves a major muscle group (chest) and uses 2 primary joints (elbow, shoulder).
Assistance exercises usually recruit smaller muscle groups (upper arm, abs, calf, neck, forearm, lower back, lower leg), involve only one primary joint and are generally less-important in improving athletic performance alone. An example of an "Assistance Exercise" would be a bicep curl as it mainly works the muscles of the upper arm, and only acts upon one primary joint (elbow).
Structural exercises are those that directly or indirectly load the spine in some way. A back squat for example places the resistive load directly on the spine causing many muscles to be involved in keeping a rigid torso.
Structural exercises that are performed very quickly are known as "power exercises". A good example of this would be a power clean. Power exercises are a fantastic way to practice sport-specific movements while creating a strong midsection and developing strong, powerful muscles!
Movement Analysis of the Sport
This stage is especially important and related to "Step 1: Needs Analysis" as an individual who trains in resistance movements that are as closely related to their sport-related performance as possible, the more likely their performance will increase. This is known as the "specific adaptation to imposed demands" (SAID) principle.
For example, a sprinter or competitive runner will see tremendous benefits from using weighted lunges in their training as the correct muscle set is involved in both the training and performance of sprinting.
One thing that can not be overlooked however, is muscular balance. Certain muscles not only act as agonists (primary movers) in a movement, but can also act as antagonists to other actions, or sort of a braking mechanism. For example, when you throw a baseball, your triceps muscle is involved in extending your arm at your elbow. As your arm extends, your bicep acts as one of these braking mechanisms in order for your elbow to not hyper-extend. If however, a baseball player strengthens their tricep muscles more than their bicep muscles, they can create a disparity between the two and can increase the likelihood of injury.
Besides muscular imbalance within a limb such as the previous example, muscular imbalance can also be detrimental to athletes who swing a piece of equipment for example. Golfers, baseball players, etc. can experience muscular imbalance as one side of their body may be stronger than the other to develop torsional power. If a well-balanced resistance training program is not implemented, one side of the body will continue to be stronger which can also lead to injury.
Exercise Technique Experience
Very basic theory here, if an athlete does not know how to perform an exercise with correct form and safety, then they should be instructed on how to correctly perform said exercise, and then start off with just small increases in intensity. For example, a distance runner may not have experience in the weight room, and has never done weighted lunges before. They should start off first learning what the correct form of a lunge is, then slowly adding weight as they improve strength and form.