Max Strength
Max strength is the maximum amount of force the athlete can produce in a specific movement, regardless of time constrictions. For example, max strength in the squat is the highest amount of weight an athlete can successfully squat in the full range of motion for a single repetition. In sports where the athletes need to move their body through space (e.g. sports involving sprinting, jumping and changes of direction) and in sports with weight divisions (sports like martial arts and weightlifting), the specific variable that matters is max strength relative to the athlete’s bodyweight, otherwise referred to as “relative strength”. For example, the relative strength of an 80 kg athlete with a 120 kg squat is 1.5 times his bodyweight (1.5xBW). If that athlete were to improve to a 140 kg squat while gaining 5 kg of bodyweight, his relative strength would improve to 1.65xBW, which is advantageous. If, on the other hand, he were to improve to a 140 kg squat while gaining 15 kg of bodyweight, his relative strength would decline to 1.47xBW and that would be disadvantageous. It should be noted that, regardless of gains in relative strength, bodyweight gains should also be weighed against any possible impact the added body mass may have on the athlete’s endurance.
Heavy strength training can transfer towards increased power production and a higher vertical jump.
It needs to be noted that max strength production is independent of time (in the max squat example, it doesn’t matter how many seconds the lift is completed in) and for that reason max strength is not directly applicable to most sports, since in most sport situations force needs to be produced and applied within very short timeframes. From the moment muscle contraction is initiated it generally takes over 300-400 milliseconds for max force to be produced. In most sports movements, like accelerations, changes of direction, jumps, throws and martial arts movements (strikes and take-downs), only a fraction of that time (typically between 100-300 milliseconds) is available for force production and therefore only the force produced in that limited timeframe is what directly influences performance. Exceptions, where max strength is indeed directly relevant, are sports that include instances where strength is developed in longer timeframes, with examples like the iron cross in gymnastics, resisting a hold in grappling and the first strokes of a race in rowing.
Despite the fact that it doesn’t directly influence performance, max strength is an important training variable in athletic development. Through properly designed training, greater max strength will translate to greater explosive strength (greater force applied in the short timeframes that matter), because the greater the difference between explosive strength and max strength the easier it is to increase explosive strength. This difference between explosive and max strength is called the “explosive strength deficit” and it shows the percentage of max strength potential not used during the specific explosive action. When the explosive strength deficit is large, the athlete is “stronger than he is fast” and the most effective option would be to put a greater focus in explosive power development, whereas when the explosive strength deficit is small, the athlete is “faster than he is strong” and the better option would be to place a greater emphasis on max strength development. Max strength is mainly trained in a general way, using basic compound exercises that can be easily and safely loaded in an incremental fashion (squats, deadlifts and presses being the main core of basic strength training) and using heavy weights for low numbers of repetitions.
To return to the race car analogy, max strength is the size of the engine and, while a larger engine doesn’t automatically ensure greater horsepower, a larger engine will allow for greater power production if properly designed and applied.
Explosive Strength/Power
Power is the rate at which work is produced and is defined as the amount of work performed divided by the amount of time it took (P = dW / dt, where P = power, W = work and t = time). In explosive sports movements, power production depends on the amount of force the athlete can produce in the short timeframe for force application, commonly referred to as “explosive strength”, and it directly influences how quickly/ explosively the movement is performed. For example, in the vertical jump, the greater the force the athlete can produce within the ~200-300 milliseconds of force application, the greater the power production and thus the higher the jump is going to be. Explosive strength is the “holy grail” of athletic preparation for dynamic sports as it directly influences all explosive movements (how fast the athlete can accelerate, decelerate and change directions, how high he can jump, how far he can throw an implement, etc.) and can make an athlete in dynamic sports a faster and more effective machine. In the initial analogy, explosive strength/power is the actual horsepower of the race car: assuming max strength determines the top speed the car can eventually reach (i.e. the max amount of force your body can produce independent of time), explosive strength/power would determine how fast the car can accelerate from 0-100 km/h (i.e. how much force/ work can be produced in limited timeframes).
Track & field athletes exhibit awe-inspiring levels of explosive power, developed through years of performance-focused strength and power training.
While max strength is a more general and relatively more straight-forward parameter in terms of how it should be developed, explosive strength/power is much more dependent on the specific movements performed and a number of different physiological parameters need to be taken into account when designing the power development training program (whether the “weakest link” of the athlete is his max strength or his rate of force development, whether the particular sports movement requires explosive force production from a dead start or whether a stretch-shortening muscle action is involved, what the length of the timeframe for force application is in the particular movement, what the amount of load used is, what are the specific joint angles and ranges of motion, etc.). There is a vast array of different exercises that can be used to develop the athlete’s power production, including basic olympic lifts (e.g. power cleans and power snatches) for general hip extension power production, basic sprinting and jumping exercises, throwing exercises (e.g. med ball throws), various different plyometric exercises (e.g. bounds, hurdle work and depth jumps) and even basic strength exercises performed in an explosive manner (e.g. dynamic effort work with or without accommodating resistance modalities like resistance bands and chains). The job of a knowledgeable and experienced S&C coach is to create an effective power development program that factors in the specific physical condition of the athlete and the specific physiological and biomechanical demands of the athlete’s main sport.
