Allow me explain what three-dimensional means when it comes to exercise programmes and why it is important. There are three planes of movement our bodies can move in, forwards and backwards (sagittal plane), sideways (frontal plane) and rotational movements (transverse plane). By following a programme dominated in the sagittal plane (a forward and backward movement), a weakness in the other two planes develop which is very common as almost all gym machines move in the sagittal plane. Gym machines normally dominate a typical exercise programme for sportspeople. A good level of strength should be the minimum requirement in all three planes of movement for all people wanting to excel in sports and reach their optimal potential.
Fixed resistance machines will never be the best tools for training with for someone who engages in a sport because the stabilising and core muscles are made redundant whilst the prime movers (the muscle group(s) needed for the movement) get stronger. In a functional sense this is absurd when you think about it because the activation of the core is always required to stabilise and help protect the back when engaged in sports.
Any training that widens the gap of prime movers over stabilising muscles puts the person at a higher risk of injury. Also strength, speed and agility are compromised due to an ever-increasing weak link from the consequences of training on machines. A non-functional programme that excludes using the core muscles slows the rate of progression because it is the core muscles that stabilises the body every time the arms and legs are working.
To summarise, exercise machines require you to push or pull in a fixed motion causing the superficial bigger muscles (the prime movers) to get worked but leaving the smaller stabilising and core muscles virtually untouched because the bolts, rails and back rest are taking the load away from these important stabilising muscles.
Swiss balls, dumbbells, barbells, medicine balls and cables all have unrestricted motion in any direction and are the preferred tools to build a functional body. Whichever sport you are involved in needs analysing so the training style can be tailored to face the challenges of what the sport brings.