The classical definition of strength as the ability to exert force defines strength in an isolated laboratory setting, but we need to apply strength to the sport or activity we are preparing for. That definition obviously has no time constraints in how long it takes to exert the force. I think Frans Bosch’s definition of strength, as coordination training with resistance is a step forward. But it needs a bit more qualification to adapt to all situations. I define strength training as coordination training with appropriate resistance. Appropriate is determined by the demands of the sport, the position or event, the qualities of the athlete and any injury prevention considerations. If you are a shot putter or an American football lineman then you will have to overcome significant external resistance to be effective. Therefore your strength training program should be biased toward heavier loading at certain key phases of the training year. Conversely if you are a sprinter or a tennis player the opposite is true. There will still be some loading, but in a very small proportion to the entire training program. The goal is strength that you can use in the actual sport activity, not just measurable strength in a controlled environment, although that is part of it. In both instances though the loading must be systematically varied to enhance coordination, which cannot be compromised if you want the strength gains to transfer.
Coordination implies the ability to reduce and produce force in a proprioceptively enriched environment in multiple planes of motion, at multiple joints all at the correct time to efficiently achieve execution of the required task in the least amount of time. Strength and coordination go hand in glove. The two qualities are more than complementary; they are the yin and yang. The challenge is determining appropriate load, it is more art than science. It is very labor intensive, demanding coaching on every rep and every set so that adjustments in loading can be made. Chasing numbers won’t do it. 1 rep maxes are cool but not an accurate reflection of applied strength gains outside of actual lifting. Maximums indicate trends, not transfer to the sport performance unless you are coaching power lifting or weight lifting.
My frustration starting with my time as an athlete and extending deep into my coaching career was to see a commensurate return in performance from the time I invested in strength training. In many respects this is an endless search, but thinking of strength training as coordination training with appropriate resistance is a giant step forward. If nothing else it will make us more efficient in utilization of time, along with a greater chance of transfer. We need to challenge ourselves in the area of strength training, to break away from conventional wisdom and seek out new possibilities for improvement. This approach has challenged me.