In Part 1 of this article, we took a crash course in motor learning, which is the process by which the body learns and retains movement skills. Your personal training clients rely on both internal and external feedback when learning a new skill, and your feedback can be critical for a client’s success in truly integrating a new movement skill. Evidence suggests that when coaching a client through an exercise, verbal cueing should be applied first, followed by visual, with tactile feedback used as a last resort. Evidence also suggests that clients who are cued in-between sets rather than during, show greater long-term skill retention.
With that in mind, let's move on to how you can work with clients to advance their performance using a variety of training variables that can be tailored based on your ongoing assessment of their stage of skill development and overall progress in training.
One of the challenges trainers face daily is the selection of exercises appropriate to the client’s fitness and skill level. While easy exercises may not challenge the client enough to cause adaptation, exceedingly difficult exercises may be impossible for the client to perform at all. Ideally, you should keep a client in the associative stage of learning for a significant portion of the training session.
As mentioned in Part 1, the associative stage is marked by the movement being performed correctly for the most part, with some error. For the safety of the client, there should be an inverse relationship between the amount of error expected and exercise intensity, meaning exercises that still cause significant error are not to be performed with heavy weights.
It is important that the methodical observation and coaching techniques explained thus far are followed by an equally methodical approach to exercise selection. Using the variables described below, you should be able to alter exercises in accordance to the developing skill sets of your clients.
The complexity of exercises is raised by increasing the number of motor units necessary to perform the exercise. A simple way of doing this is to increase the number of joints at work during the exercise. The cable push-down and close-grip bench press are both excellent tricep exercises. The close-grip bench press, however, recruits more total motor units by adding shoulder flexion as well as elbow extension, making it a more advanced movement.
Increasing the number of motor units also increases force production, allowing more resistance to be used, further enhancing the training effect. Another technique for increasing complexity is to go from a bilateral load such as a barbell bench press to a unilateral load such as a dumbbell bench press. Having the hands independently loaded forces the client to recruit more motor units to accomplish a similar task.
The modality of exercise also has a lot to do with the complexity. As a general rule when prescribing an exercise, selectorized machines tend to be most simple, followed by cables, followed by free weights.
Stability training is a popular term used in fitness centers today. It is normally used to describe the use of tools such as stability balls, mats and wobble boards. The term “stability” when used in biomechanics is simply a measure how well equilibrium is maintained. When a body is “stable,” the center of gravity is being kept over the base of support. By increasing the difficulty of maintaining equilibrium (decreasing stability) we can make an exercise more challenging.
Although “stability” and “complexity” are not to be used interchangeably, there is a close relationship between the two. Decreasing stability frequently raises the complexity of an exercise because more motor units are typically called on to maintain equilibrium. Increasing complexity however may not have any effect on stability if the relationship between center of gravity and base of support remains unchanged. Although the aforementioned tools have their place, decreasing the stability can be as simple as performing the same exercise standing instead of sitting.
In practical terms, exercises performed either seated or lying down are the most stable. Exercises performed standing up are less stable. Exercises where force is applied in any direction other than straight down (such as a standing cable chest press) are even less stable. Exercises performed on balance or “wobble” boards, inflatable disks, or mats are the least stable.
Fitt’s law (1967) states that there is a speed/accuracy trade-off for all motor skills. Simply put, the faster an exercise is performed, the harder it becomes to maintain accuracy. Weight training is typically taught in a slow, controlled fashion. For the novice client or beginning trainer, this advice remains sound. As the client’s fitness increases, speed can become yet another variable used to increase difficulty. Using the equation for force (Force = Mass x Acceleration) we see that lifting a weight quickly requires greater force production and thus greater motor unit recruitment then lifting the same weight slowly.
Going from a squat to a jump, a bench press to a medicine ball throw or a push-up to a clapping pushup are all simple ways to increase speed.
Exercisers in the fitness center setting typically perform in a closed-skill manner. In a squat, for example, the client has to adapt to the spatial conditions of the environment but there are no temporal demands. To add a temporal quality to the exercise, the trainer would find a way to make the client adapt to moving objects within the environment.
For example, you could pass a medicine ball to the client and have them throw it back during a squat or a lunge. Forcing the client to react to the ball along with the effects of the extra movement on the center of gravity significantly increases motor unit recruitment.
Assess for Success
To be able to apply this information to your clients, you must constantly evaluate them. Initial fitness assessments are important, but not as important as day-to-day evaluation during training. Detailed record-keeping is an indispensable tool. You should not only record exercises, weights and sets, but also take notes on the quality of the movements and determine the reasons for mistakes. If you think back in your training history, you can probably remember numerous examples of your clients being unable to master a particular movement. You may not have known at the time the reason for the errors.
A client who is unable to perform a movement for morphological reasons (i.e. poor flexibility) will not benefit from further coaching. A client who is physically able yet doesn’t understand your instructions will likewise not benefit from corrective exercise prescription. In order to find out the difference, try a similar skill with the same physical requirements yet different recruitment pattern (i.e. standing vs. walking lunge) If the client is able to perform one but not the other, it is likely there is a coaching issue involved because he or she is demonstrating the physical substrates necessary for the walking lunge while performing the standing lunge, and vice versa.
A common example is the client who is unable to reach parallel in a squat (crease of hip parallel to top of knee). The most common explanation for this condition is poor flexibility. But imagine if the client were told to lie down on his back, and bring the knees towards the chest without rounding the back. What if they could, indeed, break parallel in this manner? It would indicate that the lack of flexibility was NOT to blame. It could be weakness or amisunderstanding of the coaching cues given.
Real World Scenario
Let's say you have a client who is unable to perform a lunge at your direction.
First, make sure that the client understands your instructions. Try re-wording your cues to find out if this helps. If this fails, move on to visual and eventually tactile cueing. If you are sure that the client understands the demands of the exercise but is still unable to perform it, then you must consider other reasons for their inability to perform the task.
Do they have a flexibility or strength issue inhibiting movement? If so, try a variation of the movement such as a step-up, and add exercises that will correct the weakness/imbalance. Are they being overly cautious for fear of falling? Find out what the fear is and alter the exercise to build confidence. Try going from a lunge to split squat. The range of motion is the same but it may feel safer without the momentary loss of balance during the step.
Analyze the nature of the task. Lunging in place is a discrete skill while walking lunges are a continuous skill. Does the client find one more difficult than the other?
OK, he’s got it. Where do we go from here?
Once the client has learned the chosen exercise (the lunge), there are many ways to advance the skill, including:
- Decrease stability by having the client walk a line while lunging. This will decrease stability in the frontal plane.
- Add a barbell shoulder press to each lunge. Multi-tasking will increase the complexity.
- Make the client jump and switch their feet in between lunges. The jumps will add a power element and the speed required will make the lunge more difficult.
- Put three targets on the floor and instruct the client to lunge to a different target on each rep, adding inter-trial variability.
- Take the skill from closed to open by tossing them a ball at the bottom of each lunge and have them toss it back at the top.
Clients learning new skill go through distinct stages of learning. It is important to be able to recognize these stages and program exercises accordingly.
Errors play an important role in learning by providing feedback to the learner. As long as risk is minimal clients should be allowed to “work through” mistakes rather than be immediately corrected.
Learners will make errors for a variety of reasons. The trainer must be able to identify why errors are being made to identify solutions.
Complexity, stability, modality, and speed are all factors which may be altered to advance an exercise and the client's movement skillset.
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- Fitts, P.M. (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47, 381-391.
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