It´s a great pleasure to publish this interview with Dr. Eyal Lederman! Mr. Lederman is the director of CPDO, a practicing osteopath since 1986, and has a PhD in physiotherapy. He is also a world-renowned researcher, lecturer and author. Dr. Lederman´s latest book is Therapeutic Stretching: Towards a Functional Approach, and after reading it I decided to contact him and ask if he wanted to answer a few stretching-related questions from me and K3´s readership. He did, so enjoy!
– Dear Readers, the answers to the questions raised below have been discussed extensively in my book Therapeutic Stretching: Towards a Functional Approach. The preface and first chapter can be downloaded from here.
The science of stretching seems to have changed quite dramatically in recent years. What, in your view, are the most important changes to ”old” ideas that have come out of stretching-related studies during the last five-to-ten years?
– There are several prevalent assumptions associated with stretching:
• ROM recovery – stretching is essential to ROM recovery following immobilisation or contractures
• Enhance physical performance – stretching improves physical performance of a wide range of daily activities or sports related activities; from cardiovascular related activities (e.g. running) to resistance training (weights etc.). It is often suggested this could happen via biomechanical or motor control optimisation
• Injury prevention – stretching prevents injury by either altering the biomechanical properties of muscle and connective tissues, or by improving human performance
• Pain alleviation – stretching can alleviate pain, such as reducing the duration or level of DOMS or low back pain
– Research in the last decade has refuted all these assumptions. Stretching itself seems to be in a critical condition! We need to view ROM loss and recovery as a multidimensional adaptive process spanning tissue and motor control changes and driven by the individual’s behaviour. Perhaps this is where the problem is with many stretching approaches – they lack a multidimensional expanse.
– However, we are still left with a major clinical problem – how to help individuals recover ROM losses, such as seen in contractures and after immobilisation. There is mounting evidence that promoting performance of daily or sports activities at end-ranges (Functional Stretching) may provide the solution for ROM rehabilitation. This approach is similar to the training principles used for enhancing sports performance, i.e. specificity, overloading and repetition. This is something that we are currently researching at University College London (UCL), and the proposed stretching approach promoted in my book.
What are the key points that physically active people should bear in mind around stretching or mobility work? ”To stretch or not to stretch” – are there any plus sides left? 😉
– Adaptation in the body is activity specific. It provides a unique and optimal physiological, neuromuscular/motor control support for that activity. So running training enhances running performance, cycling enhances cycling, tennis improves tennis and so on. However, there are no carry-over gains from one form of activity to another, i.e. tennis is unlikely to improve cycling, etc.
– Along this line of unique physiological adaptation, a functional stretching approach may be useful for an acrobat, dancer or martial arts expert, but is unlikely to improve activities in which agility is not required. Hence, stretching is superfluous for most sports activities; it is more a social-cultural trend rather than a physiological necessity (I run daily and never perform a single stretch, without any ill effects).
What is your view on the practice of foam rolling / so-called self-myofascial release that is commonly practiced among fitness folk these days? It seems to work by increasing ROM when done before training, and perhaps by aiding recovery when done after training, but nobody knows exactly why, there´s just practical insights from gyms around the world.. Do you have / are you in favor of a particular theory on why this seems to work?
– There are several mechanisms by which ROM can change:
• Biomechanical – by creep deformation. This a transient change in the stiffness of tissues in response to mechanical loading. This would happen with any tissue loading even resistance training. It is not unique to stretching. Such biomechanical ROM related change will happen immediately as the person begins the sporting activity. It is usually short lived, lasting less than an hour after the termination of loading.
• Biological-adaptive – another mechanism for ROM change is related to adaptive changes in muscle and connective tissues. In response to prolong loading the tissue’s biomechanical properties change. However, these adaptive tissue processes are expected to occur over weeks and months, so this is an unlikely to be the mechanism for the immediate ROM increase.
• Stretch tolerance – More recently several studies suggest that ROM increases after stretching are associated with the person becoming more accustomed to and “less concerned” about the discomfort and pain of stretching. This mechanism could explain the ROM experience with myofascial techniques, in particular if they are painful.
• Placebo – my preferred explanation for the phenomenon described above
Reader question: Does Mr Lederman see it as problematic that the primary focus of ”traditional” stretching is to increase ROM? Would a more natural progression be to incorporate more of an ”expression-filled” practice, think ”Ginastica Natural” etc. This would bring more focus on skill as well as add some ”soulfulness” to mobility training.
– There are many reasons for people to take up stretching. They can be divided into broad groups – recreational (including sport activities), professional (ballet dancer, professional acrobats) and therapeutic. Most individual in these groups use stretching to either maintain or improve their agility (ROM) or to improve physical performance by improving agility (again ROM). However, within the recreational group many individuals use stretching for social contact (Yoga), pleasure, sense of wellbeing, relaxation and even for spiritual reasons, e.g. opening chakras as in Yoga or facilitating flow of energy as in Tai-Chi.
– I am interested in the therapeutic aspect of stretching for ROM rehabilitation. Traditional stretching has proven to be ineffective for this purpose. We need to rethink stretching. I provide an alternative called functional stretching. This approach uses the individual’s own movement repertoire to overcome ROM losses. It is a behavioural-functional approach in which the individual is encouraged to use daily activities to provide the ROM challenges. For example, an individual who has lost dorsiflexion ROM of the ankle is encouraged to amplify daily activities that challenge dorsiflexion, say walking with wider gait, increase stair climbing, weight bearing on the effected side when getting up from sitting and so on. This form of elevated daily activity I call Functioncise.
Reader question: How much should one stretch with hypermobile joints?
– No other animal stretches except humans. There are no known physiological advantages to stretching nor does it enhance human performance. If it was advantageous it is likely to have been “factored-in” into animal behaviour. It seems that daily functional loading maintains the agility required to carry out these tasks, i.e. by bending to lift, sitting flexed and twisting to turn we maintain the flexibility of the spine to carry out these activities.
– This brings us to hypermobility. A hypermobile individual is unlikely to lose their flexibility by not stretching. Furthermore, we can assume that their functional ROM will be maintained by daily activities. So the question is why would a person that has “excessive” ROM engage in an activity that would increase it even further? Logic would suggest that stretching in hypermobility is unnecessary unless the person does it as part of general health care/fitness and derives pleasure and other psychological benefits from it such as sense of wellbeing, relaxation, etc.
Reader question: How does stretching affect the energy levels or metabolism of a muscle? If a muscle is ”tight”, can it´s metabolism be improved by stretching it out?
– I am not sure about the relationship between muscle tightness and metabolism. It might be an area of research that I have missed in my exploration of stretching. Let’s look at what we know about muscle tightness. A muscle may be tight for several reasons:
• Adaptive long term changes in structural and biomechanical properties (it becomes physically tight, e.g. after immobilisation
• increase in stretch sensitivity (it just feels tight but there are no real changes in biomechanical properties)
• After an acute bout of exercise or stretching (DOMS) or injury (oedema etc.).
– Metabolic factors are unlikely to be a significant factor in the adaptive-biomechanical or stretch sensitivity related tightness. As far as DOMS, tightness could be related to sarcomere damage, an increase in interstitial fluid combined with an increase in stretch sensitivity. In more extreme cases it may even be associated with haematoma within the muscle. It is difficult to imagine how recovery from DOMS would benefit from stretching. Moreover, it is well documented that stretching before or after exercise does not seem to have any effect on DOMS. In fact, traumatised or DOMS affected muscle may be further damaged by stretching (see below).
– As far as metabolic activity, we would expect metabolic activity to increase in an actively contracting muscle. Hence, active stretching approaches such as muscle energy techniques, ballistic stretching or some form of dynamic active stretching are likely to result in metabolic responses. However, this is less likely to happen if the muscle is stretched passively.
Reader question: What is the best time to stretch around strength training? Immediately after training, or should one take a break and then stretch?
– As discussed above, stretching does not enhance performance in activities that do not require flexibility. So there is no point in stretching before or after resistance training. Furthermore, studies in the last few years have shown that vigorous bouts of stretching before sports activities tend to reduce power output and therefore degrades athletic performance rather than enhance it, probably by inflicting sarcomere damage. So, if you enjoy stretching just continue as and when you wish, but just do it more gently..
More on the topic:
Paul Ingraham´s article Quite a Stretch
For information on functional stretching courses, check out the CPDO website.