When to Implement Flexibility into a Workout
Flexibility is technically defined as the ability of a joint to move through a full range of motion (ROM) around its axis. However, a lack of flexibility at a given joint can negatively impact all the surrounding tissues. Mechanics are based on moving parts and stabilizing segments, and when dysfunction occurs it affects the kinetic chain. Flexibility plays a major role in posture, joint function, muscle recovery, reducing the risk for injury, and optimal performance during physical activity. Static, dynamic, ballistic, active-assisted and proprioceptive neuromuscular facilitation (PNF) stretches as well as various myofascial release techniques can be used to enhance ROM. Fitness professionals unfamiliar with the science behind flexibility will not understand how each technique functions as a potential tool for improvement, and may find themselves making poor decisions based on a client’s needs. Static/active-assisted and dynamic stretches are among the most popular stretching activities employed on a regular basis. Additionally, foam rolling and accupressure techniques for fascial restriction have gained popularity but few understand the alleviation mechanisms associated with the nervous system.
So when and how often should a personal trainer implement these activities for optimal results? The ultimate goal of a given program, as well as any special client needs, can warrant modification to any component of a training session; but the following recommendations can usually be applied with confidence. In all cases, the trainer must consider the type of client they are working with, individual capacities and risk factors, and what will optimize their success in the program.
Static or active-assisted stretches: Static stretching seems to be best applied at the end of an exercise bout or using reciprocal tactics at the end of a training segment such as stretching the pectoralis following a pulling exercise. Conceptually static stretching is best applied with a goal of reducing tension when connective tissues have been properly warmed up. Tendons and ligaments experience greater plasticity and lower viscosity when they are warm, which allows for a better stretch. Applying static stretches to tissues that are cold (and not previously activated) minimizes the potential for tissue elongation, and may even increase the risk for injury if too aggressively applied. Therefore static stretches should not be applied at the beginning of the workout or before an anaerobic event. In most cases these stretches are best used as part of a cool down. Research has clearly shown that the performance of static stretches immediately prior to power or strength endeavors can negative impact force production and velocity, particularly in lower body exercises. This points to the common error in exercise order used in sports and fitness when people static stretch as a warm-up component. Runners may employ static stretches before a workout, following a warm-up, as jogging is a low tension activity, but dynamic applications still seem to be superior. Likewise, an injured athlete may warm-up and then isolatively stretch the high risk area to help reduce restriction during activity. In this case though, a professional should supervise the activity and the motion segment must then be placed back in a progressive warm-up to re-stimulate the nervous system. Likewise for higher risk clients such as the elderly, who will not produce significant force, it may well serve as part of a general preparation period for a client who is simply trying to improve measures of health and benefits more from mobility.
Dynamic stretches: Progressive dynamic stretching is best applied as part of a specific/functional warm-up prior to the training segment to increase body temperature, pre-activate the musculature to be used during the workout, and prepare the nervous system for demanding work. When properly applied, it is very effective at improving acute ROM for the movement patterns. For this reason, personal trainers should incorporate actions that mimic lifts or activities in whole or in part, that will be performed in the program as well as movements where the client has difficulty maintaining proper form with external loads. Dynamic stretches do not seem to create any reduction in power or force output potential as seen with static stretches but do enhance movement range and empirically reduce risk for injury.
Foam rolling (and related techniques): Activities that aim to reduce myofascial restriction can be applied before and after training as needed. They do not seem to limit performance when applied prior to intense lifting or power training as seen with static stretches. Conversely, removing restriction before a training session can reduce the risk for acute strain and help muscles work cooperatively without the presence of compensatory movements/activation patterns. The same techniques can be applied again after training to help facilitate recovery and muscle relaxation. Foam rolling should be performed prior to a workout, even though it is not considered as part of the warm-up, as no temperature change or ROM is attained.