Mobility training is considered to be an integral part of most athletic training programmes, with several different approaches and beliefs leading to distinct implementations. These differences may compromise the communication between a newly formed team that, due to the different approaches/beliefs, may value distinct priorities in this training component.
This type of training comprises modalities such as stretching (e.g. static and dynamic – both under active or passive tension), articular banded mobilizations and foam rolling. Although these wide spread strategies are well established in football, there still exists a huge debate as to the importance of mobility training and its effects/consequences (e.g. due to its acute and potentially harmful effects on performance of high intensity, rapid-stretch shortening actions (i.e. sprinting) as well as maximal strength actions. This raises some specific questions as to how and when these should be implemented within the training program.
The purpose of this chapter is to address the mechanisms by which mobility training can be an adjunct to the training program (i.e. neural, viscoelasticity – articular and muscle-tendon extensibility) as well as discussing the issues surrounding its indiscriminate use within the football training microcycle.
Mechanisms of stretching
Harvesting all the inputs, whether neural or mechanical
Traditionally, stretching techniques are classified as static or dynamic, in which the stretch is either held or it is combined with the mobilization of the segments of the body, respectively. Although this classification is commonly used in football, it doesn’t determine the kind of muscular tension that the athlete is exposed to, being this the reason why we consider it to be rather incomplete and misleading. It’s also why, in the following chapter, we will characterize the stretching by how it is performed: either with passive or active tension.
In a passive tension stretch, we look for a complete relaxation of the targeted muscle, while lengthening it until a stretch sensation or point of discomfort is felt, holding that position for a given period of time.The proposed mechanisms by which static passive tension stretches work are both mechanical and neural.
Mechanical effects have been suggested for passive stretching, such as decreased passive torque of the muscle. However, this has only been demonstrated when performed by an elevated amount of time (e.g. > 6 minutes of continuous stretching) which is considerably higher than most common stretching durations commonly performed on football practice. In fact, these effects seem to be acute and transient in nature, with no significant impact on posterior function (Kubo, Kanehisa, Kawakami, & Fukunaga, 2001) (Magnusson, Simonsen, Aagaard, Sørensen, & Kjaer, 1996)
When we consider the neural effects, we are considering the impact that the nervous system has on the muscle tone. Prolonged static modes of stretching can inhibit/desensitize spindle reflexes (e.g. due to the accommodation phenomenon of the intrafusal fibres) inducing pre and postsynaptic inhibition of the peripheral afferents. This static stretch-induced reduction in muscle activity can be associated with the subjective reported sensation of reduced soreness. This also gives us a clue on how and why prolonged static stretching may negatively affect acute performance. Although this may be detrimental before competition, some studies showed that following this kind of stretching, there is a greater parasympathetic influence which can positively influence both recovery and adaptation post-exercise adaptation (e.g. decreasing cortisol levels, catabolic hormone, immune system depression).
Opposite to this is the active tension stretch.This stretching is done whilst the muscle is contracting, either isometrically through different and progressive muscle ranges or eccentrically.
One way to promote stretching with active tension of the muscle is using vibration devices (e.g. such as vibratory platforms, foam rollers, etc). When exposed to vibration, the muscle contracts due to the vibratory tonic reflex (i.e. vibration frequencies of > 30 Hz).This vibration-induced improvement in ROM has been justified by a multitude of factors, such as the increase in blood flow and in temperature, thus resulting in a decrease in muscle viscosity and passive torque. Other justification is the role of presynaptic inhibition and concomitant decrease in reflexive activity. This is a rather innovative stretching modality, gaining interest among clinicians and researchers since the combination static stretch + vibration appears to surpass the potential detrimental effects seen with prolonged static stretching, while still achieving the acute articular range goals. (Jemni, Mkaouer, Marina, Asllani, & Sands, 2014).
The overall goal (and source of benefit) of the active tension stretching is to recruit the muscle throughout its entire range and, with this, increasing the neural awareness (which, in contrast to the passive stretch, isn’t associated to a post-stretch inhibition) as well as inducing some viscosity changes in the elastic elements of the muscle but also of the tendon and surrounding tissue. This has a special importance since mobility may be restricted not only due to the muscle fascicles but also due to tendon, aponeuroses or joint capsule changes.
The explanation for why these are special characteristics of active stretching modalities (in comparison to passive ones) are easily understood by the work from (A. J. Blazevich et al., 2012), which found muscle tissue to be more compliant than tendon (14,9% to 8,4% respectively), meaning that in order to stretch the stiffer component – tendon – the stiffness of the muscle tendon unit (MTU) has to be increased. We also know that fast velocity actions and rapid-stretch shortening cycle (SSC), will increase stiffness of the MTU, so we can address that by using slower modes of contraction like isometric ones, that can help to induce some acute transient effects on the MTU. Thus changes in acute MTU stiffness elicited by active stretching may influence athletic performance/injury risk and therefore optimizing tissue stiffness (i.e. alongside other modalities such as # exposures and distance covered at % of max velocity – which will be covered on following chapters) is an important health and performance goal. As a rule of thumb, the variables that increase tendinous stiffness are: longer contraction durations (time under tension), outer range contraction (long muscle length) so we can address this on our planning to induce the changes we want pre-training or as chronic long term changes (Oranchuk, Storey, Nelson, & Cronin, 2019).
Why is this important? Because if we consider that different players have different physical characteristics and requirements, we can aim to potentiate these. For example, in the case of a particularly fast player -meaning that he presents with high stiffness of the MTU- we should seek for active tension stretching techniques under isometric contraction types, to target the MTU viscoelasticity and the said acute effects.
Not only do athletes have special requirements but also in the same athlete we should consider that different joints and muscle groups have different needs and there isn’t a “one size fits all” solution. One example is muscles that exert high levels of tension throughout large ranges of motion and that contain a high collagen content (e.g. such as the hamstrings) should be given focus towards active tension stretches. This “need” is due to the fact that these types of muscles are prone to reduce their extensibility and have been shown to be sensitive in players under increased loads/match congestions.
These reductions in range (such as in the Bent Knee Fall out Test, total hip rotation ROM loading the adductor muscle groups, the anterior hip capsule and deep internal rotators) have also been shown to be associated with higher risks of muscle strain and therefore something to be addressed in these movement preparation routines. (Tak et al., 2017);
Take the best use of this moment, not only for what it represents physiologically to the athlete but for the information you can retrieve from observing the athlete performing the routine. Since the routine includes a series of structured patterns that are relevant for the sport, it is also a great moment to screen the comfort and easiness that athlete presents while performing the exercises. This continuous screen of the relevant movements allows the coach and medical department to compare, not only between different days of the weekly microcycle but also throughout the different mesocycles and different times of the season. Besides the “external assessment”, the athlete should also be instructed to pay attention to this moment and “auto-assess” his own state; this allows for a “mindful” preparation for the movement and, with this, a safer start.
Explaining what we mean by “safer start”, imagine the following scenario: if the athlete uncovers a tight hamstring during his routine, he may take it easy in the first high velocity runs, communicate the feeling with the clinical department and coach and, together, contextualize this feeling with other information from the athletes profile (such as the load he has been imposed and feeling – GPS, RPE, among other tools). After this, the decision is done by the team and, eventually, if decided that the player should engage in the training and the “tightness” feeling fades away, there is nothing to worry about and the team responsibles (clinical, coach and athlete) are already aware of what happened. What could happen, if the routine is done without any “self-attention”, is that the athlete only uncovers the same tightness feeling during a high velocity runs and, associating it to the runs, starts guarding the movement and eventually missing the rest of training session, afraid that the feeling may be the symptoms of a new acute injury.
Is it so wrong or harmful to stretch before any sport activity?
When we mentioned the different approaches and beliefs ingrained in the football culture, pre-activity stretches take a key role.
If we look at the science, the literature shows strong evidence supporting performance impairments when we stretch for longer than 90s. However, if we reduce the total stretching duration to a maximum of 90s, the evidence is unclear, with a disparity in the conclusions Behm, D. G., & Chaouachi, A. (2011).
Two disclaimers regarding the conclusions aforementioned are the volume of the stretching and the population being studied: a total stretching duration of less than 30s has been proven to not have an impact on the subsequent performance, especially when done in highly trained athletes or when the study population had the opportunity to become familiarized with the movements of the testing protocol.
With this we intend to clear the straight idea that static stretching is for sure going to have detrimental effects and that dynamic stretches are the definite best. Regarding gains in performance due to dynamic stretches, the evidence is conflictual. On one hand, dynamic stretching has been found to improve performance (assessed in 20m sprint, jumping performance and leg extension strength), when performed for longer than 60s per muscle group; this could make it specially interesting since the requirements of football do include high speed and power related activities. This study was done comparing the two types of stretching – static and dynamic- and assessing function immediately afterwards(Behm & Chaouachi, 2011). However, other studies have found that, when performed as part of a full warm up session, neither static nor dynamic stretching appeared to affect the performance in a 20m sprint velocity or counter-movement jump height. In these studies, the two types of stretching were combined with other warm up componentes, such as running, changes of direction and so on. (Little & Williams, 2006; Taylor et al., 2009)
In order to prime the neuromuscular system for these kind of actions, our clinical experience points towards prioritizing dynamic (active) stretches that not only won‘t produce the stretch-induced impairments and, in some cases, may even potentiate performance. When thinking about implementing a static stretching program in a warm up routine (and, especially, when this precedes SSC, explosive or high strength actions) it’s wise to be cautious and consider that any decrease in performance can be determinant.
When considering impairments, we’d like to leave one last note: the possibility of detrimental effects of not performing any stretches. How come? Even without going into the physiology, we point towards something we’ve been mentioning over and over: the belief system. And although most of the times we referred these as in the coach/responsible mind, the athlete is himself not immune to these beliefs. This means that if the athlete has any type of mobility routine ingrained in his ritual, the change into some other routine (whatever the decision is) should be lead by gaining the athlete’s trust and explaining to him why the change is needed, how it is going to be done and the implications of not doing it: in other words, the athlete has to buy the new belief.
Mechanisms that explain the usefulness
Foam rolling is another proposal to affect/develop athlete ‘́s mobility. This tool/technique is, however, filled with beliefs through the entire sports medicine community. In this segment, we will try to give some clearer ideas of what is the evidence behind it and how, by knowing this, the reader may improve its effectiveness.
This intervention consists of a compression/rolling of the body over a foam-covered tube that is kept between the athletes’ body and the floor. By doing this, the entire weight of the athlete is sustained under the tube and the respective area in the body of the athlete, compressing in. Since it is a tube, it can be rolled to the subsequent body region and, with that, join the intermittent compression/decompression of the said body part.
The initial proposed mechanism of action of foam rolling was the “release” of myofascial structures by “breaking adhesions” and, therefore, allowing for the different layers of tissue to slide between each other. However, this has been proven to be an outdated mechanism and the tension that would be needed to effectively promote mechanical changes in the myofascial tissue is of a magnitude 10xs higher that the human weight. In other words, the mechanical effect on changes in fascia is highly unlikely. So how could it still be of any use?
In summary two pathways for the modification of soft tissue stiffness are proposed: on the one hand, the central nervous system is a powerful moderator of muscle tone and, by registering increases in tension and lateral stretch of the skin during rolling, promotes autogenic inhibition, leading to a reduction in muscle activity. Besides this, the mechanical maintained stimuli also affects the sensibility of the section being “worked on”. Both the inhibition reflex as well as increases in stretch tolerance may explain the improvements in ROM.
You may notice that both the above mechanisms of action are related to the motor and sensitive nervous system and not about the mechanical structural changes in the muscle being rolled (here is when we challenge the belief system previously mentioned): whilst there does exist evidence that rolling may affect local viscoelastic properties and the water content and other parameters such as blood flow in the tissue, there is also strong evidence provided by crossover or non-local rolling effects. Furthermore, there are already studies showing that even without touching the “affected muscle” (and therefore excluding any mechanical effects), rolling the contralateral muscle may decrease pain in the affected muscle. This suggests a global pain modulation (and even an increase in core temperature, due to the effort done while rolling). With this in mind, we could even ask: does it really matter to roll locally or in a specific part of the body? (Behm & Wilke, 2019; Wiewelhove et al., 2019)
Combining the effects of Foam Rolling + Stretching:
Going back to the static stretching (which, as we’ve seen improve ROM), the major concern in regards to stretch-induced impairments can be counterbalanced by the use of rolling devices, as these don‘t impair subsequent muscle strength, jump height, sprint time and fatigue endurance (Behm & Wilke, 2019; Wilke et al., 2019).
As a recommendation for rolling, the literature seems to point out that there isn’t any necessity to incur in excruciating pain (i.e. since we would need, supraphysiological tensions to induce any sort of fascial plastic changes and, with that, retrieve any mechanical changes). To achieve desired effects, rolling for as much as 30 s per muscle group (3 or more repetitions) seems to present us with the best cost-effect ratio (Behm & Wilke, 2019).
A recent study also highlights that this kind of modality can be especially important to extend the gains in ROM of a typical specific warm-up, where the augmented ROM effects were maintained for 30 minutes when the athletes performed a rolling session 10 minutes after the warm up (Hodgson, Quigley, Whitten, Reid, & Behm, 2019). This might be of use for our footballers, especially on tactical sessions, where the players might be interrupted more often and for longer periods to receive feedback, or when after a morning gym or rehab session the players go for a video or tactical speech.
Do bare in mind that implementing a mobility routine has some implications that are consistent with the precautions that any other exercise plan has and, therefore, the intensity and total load should be monitored. With this said, through this section we’ve mentioned some of the guidelines to avoid impairments and to collect the benefits but these should always follow the rule of not overloading a tissue for more than it is used to. We refer back to the previous chapter, on load management and the application of that rational for any type of stress that is imposed to the tissues: don’t create a sudden increase in load (a spike).
Besides the strategies so far mentioned, other mobility techniques may pop up (e.g. banded mobilizations, which can benefit fluid dynamics, articular lubrication and/or joint gliding, to name a few). Although, these appear to show a low degree of evidence and non consistent results, we still decided to mention them in these work proposal, because of the cost-effect benefit and since that if players positively adhere to those, that might increase the athlete self-management tools.
Implementation in the Pre-training Routine
Summing up what we’ve been through, the conclusion may not seem clear and we’d like you to be able to make an informed decision on this topic. Although benefits and potential impairments have been shown, we can’t boldly state that footballers shouldn’t stretch before competition, especially since the external validity of the different methodologies employed by some of those studies is extremely different regarding football based-environments. Here we evidence these differences in two examples
- The total stretching durations used in the studies being much longer than those typically employed by footballers (i.e stretching protocols of 15 minute or longer durations have been used for a single muscle group) (Behm, Blazevich, Kay, & McHugh, 2016);
- The stretching protocols used had extensive time-under-tension per muscle group, or used static stretching in isolation (e.g. without any period for a specific warm up such as high intensity, change of direction or some form of skill rehearsal) (A. Blazevich et al., 2018; Taylor, Sheppard, Lee, & Plummer, 2009);
So, to leave the reader with a structured recommendation and short summary of the topics mentioned, the following applies to athletes seeking or recommended to include stretch before training/competition:
- Should be guided to keep the stretches within a low repetition range and total session time dedicated to a particular muscle;
- Although the evidence isn’t fully clear on the benefits, it appears to be so regarding impairments that may be due to static stretching (if kept by prolonged times). Due to this, to harvest eventual performance benefits and because the rational appears logic and coherent with movement preparation, we recommend the focus on dynamic active stretches when preparing for a pre-activity mobility routine.
- Take into account that the expectancy beliefs regarding stretching and performance are likely prompting players to integrate them in their routines, irrespective of the type of stretch and their effects. This means that the subjective aspect of the intervention has a big part in the habit.
- Different athletes require different specificities and this also applies to the mobility routines. Remember the example of the fast player and the active tension stretch to target the viscoelasticity of the non-contractile tissue as well as MTU.
- Take into account that each muscle group plays a specific role in the movements and patterns that comprises football; this means that their routines (and, in specific in this chapter, mobility routines) should take these differences into account and aim to potentiate them.
- Use this structured mobility routines continuous movement screen moment and, with this, save time and keep track of how the athlete has been feeling/adapting. Besides this, educate the athlete to use this moment to “self-assess”.
- Last but not least, we’ve mentioned the relevance of the nervous system for several times. We’d like the reader to look at the mobility routine prior to activity as an opportunity to prepare the nervous system for movement, allowing it” to make its check up (as in the previous bullet point) and, with that, lowering unhelpful muscle tones in order to maximize both the range of motion as the muscle’s reaction in the extreme ranges.
Implementation in the Post-training Routines:
Besides preparing for activity and performance, one common topic is also how to best recover and the role of stretching/mobility. Again, the belief system goes deep in this field and it’s not unusual to hear that the athlete HAS to stretch at the end of activity, in order to prevent injury. We do hope that by now the reader has a better understanding of injury mechanisms and prevention to, at least, second guess when hearing this.
Does this mean that the athlete SHOULDN’T stretch at the end of activity? No, it does not mean this.
Although this shouldn’t be regarded as a compulsory practice, after competition/training the athlete can perform static stretching with passive tension and obtain some benefits from this. Notwithstanding, we should question their use as aiming to accelerate muscle recovery or to only use them as an adjunct to increase ROM post-training. If the latter is the goal, a combination of stretching protocols combined with vibration could be a good option, getting both the reduction in the intensity of stretching needed whilst still improving ROM and further reducing internal structure microtrauma.
Besides these benefits, this combination is also found to increase blood flow and tissue temperature. (Jemni et al., 2014) This is relevant when considering that blood flow and intramuscular hemodynamics play a crucial role in the recovery post-exercise. Taken this into account, venous return is much needed and may be promoted whilst stretching, for example, with the legs up against the wall (and therefore with gravity’s help).
The use of position dependent and hemodynamics to further increase venous return – combining low intensity active tension stretching, alongside with breathing techniques to further target parasympathetic predominance and not interfere so markedly on intramuscular hemodynamics. This can even be enhanced using water-based stretching.
Considering what we’ve mentioned above, for a post-training mobility routine, these are the bullet points that we resume as take home messages
- Mobility work isn’t a compulsory part of recovery routine and other fields may be the most relevant to focus on, such as sleep and nutrition;
- There is no evidence that stretching, if kept at a low level of intensity and range, has detrimental effects. The low level and range are in order to prevent further damage to the microstructure of the muscle that has occured after any training session;
- In fact, stretching of some musculature/muscle chains may help promoting a desensitization and reduce the DOMS perceived by the athlete;
- The parasympathetic prevalence status, induced by the routine, may have an impact on the overall recovery.
Now that we’ve been through some mobility techniques, how these affect range of motion and how to integrate these in the training schedule, we hope that the reader agrees that mobility routines shouldn’t be thought to be some kind of panacea, undertaken blindly and in disregard of individualization/small group prescriptions. With that said, we move on to the application of this valuable resource, showing one way of implementing. Below, we share a practical handout of what could be a mobility pre-training program as well as the rationale behind these:
Mobility Routines: An essential, resourceful and time-efficient in-season movement screen
One day after the Match day (MD+1) screening
Aim and characteristics of the session MD+1:
- To screen/expose abnormal areas of increased perceived tightness/soreness that may be posteriorly addressed with manual/soft tissue work or adapted gym routines throughout the training week.
- Postural restoration – the use of breathing exercises and most of the movements is done off loading the legs (supine, seated or even water based movements)
- Taking advantage of the water immersion (as the hydrostatic pressure compression of the tissues).
To have access to the photos of the exercises used in this guidelines MD+1, click here.
Two days after the Match day (MD + 2)
Aim and characteristics of the session MD+2:
- In this session, posture is key. The movement patterns targeted positively influence patterns like: Running mechanics (linear emphasis); Triple extension (explosive concentric – piston leg action); Half Kneeling (asymmetrical movement patterns); Triple flexion; anti-extension; anti-rotation
- These will allow to increase the neural recruitment of the lumbopelvic hip stabilizers, by means of the anti-rotational/extension exercises in positions that unload the lower limbs (supine, kneeling, quadruped and/or asymmetrical stances on the floor).
To have access to the photos of the exercises used in this guidelines MD+2, click here.
Three days after the Match day (MD + 3)
Aim and characteristics of the session MD+3:
- The core work predominantly is done in asymmetrical movement patterns, this time loading the lower limbs (e.g.: split);
- Other aspects are worked, such as: Single leg absorption capacity, landing/cutting skills (trunk rotation and tilt towards the stance leg, whilst cutting); single leg or asymmetrical force production (anti-extension/rotation); Upper limb pulling/pushing.
- Focusing on the postural integrity and movement patterns quality;
To have access to the photos of the exercises used in this guidelines MD+3, click here.
Two days until the Match day (MD – 2)
Aim and characteristics of the session MD-2:
- Dynamic core work, meaning that the movements imply production of rotational patterns (chops/lifts) and force production with the extremities.
- Priority is given towards unilateral force production, countermovement or double contact movement initiation.
- Explosive force production with light implements, such as a medicine ball (<3Kg) or inertial pulleys with low load, among other examples.
To have access to the photos of the exercises used in this guidelines MD-2, click here.
Consideration should be given to the types of stretching performed (e.g. static – passive, static with active tensioning of the muscle involved or dynamic) always in conjunction with timing (e.g. before, after competition and the timing for the subsequent training/competition) and it’s macro and micro-level periodisation. When used as a pre-training or match, the potential improvements in ROM, performance, and feelings of readiness might be used as a window of opportunity to further work upon dysfunctional movement patterns and different skills acquisition/motor learning. Although the literature on this subject is too diverse making it difficult to conclude on an ideal volume/intensity recommendation, it is wise to be aware and balance the above mentioned potential benefits of mobility routines, against possible performance losses (e.g. especially in high-force development activities, fast-SSC and sprinting activities), so we should stretch with a minimum effective dose (i.e. taking in consideration the athlete history and his background in the programming of tissue conditioning), as well as the organization within the warm up routine prior to training/competition.
For us, it’s also worth stating that these mobility/tissue conditioning sessions might be one of the most important and time-effective in-season movement screening for monitoring our athletes, which can give the athlete awareness about areas that should be targeted by themselves (e.g. within their tissue conditioning sessions – with rolling or stretching) or by the physiotherapists which can get a global framework of how the athlete is moving in different movement patterns and compare with the athlete ́s signature capability and variability (e.g. evaluating if it ́s a joint related, tissue extensibility or motor control dysfunction with further specific assessments) providing the athlete meaningful inputs that can truly change the outcome and quality of the training session.
READ WHAT WE READ:
Behm, D. G., Blazevich, A. J., Kay, A. D., & McHugh, M. (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review. Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquee, Nutrition et Metabolisme, 41(1), 1–11. https://doi.org/10.1139/apnm-2015-0235
Behm, D. G., & Chaouachi, A. (2011). A review of the acute effects of static and dynamic stretching on performance. European Journal of Applied Physiology, 111(11), 2633–2651. https://doi.org/10.1007/s00421-011-1879-2
Behm, D. G., & Wilke, J. (2019). Do Self-Myofascial Release Devices Release Myofascia? Rolling Mechanisms: A Narrative Review. Sports Medicine. https://doi.org/10.1007/s40279-019-01149-y
Blazevich, A., Gill, N., Kvorning, T., Kay, A., Goh, A., Hilton, B., … Behm, D. (2018). No Effect of Muscle Stretching within a Full, Dynamic Warm-up on Athletic Performance. Medicine & Science in Sports & Exercise, 50, 1. https://doi.org/10.1249/MSS.0000000000001539
Blazevich, A. J., Cannavan, D., Waugh, C. M., Fath, F., Miller, S. C., & Kay, A. D. (2012). Neuromuscular factors influencing the maximum stretch limit of the human plantar flexors. Journal of Applied Physiology, 113(9), 1446–1455. https://doi.org/10.1152/japplphysiol.00882.2012
Hodgson, D. D., Quigley, P. J., Whitten, J. H. D., Reid, J. C., & Behm, D. G. (2019). Impact of 10-Minute Interval Roller Massage on Performance and Active Range of Motion. The Journal of Strength & Conditioning Research, 33(6). Retrieved from https://journals.lww.com/nsca-jscr/Fulltext/2019/06000/Impact_of_10_Minute_Interval_Roller_Massage_on.8.aspx
Jemni, M., Mkaouer, B., Marina, M., Asllani, A., & Sands, W. A. (2014). Acute Static Vibration-Induced Stretching Enhanced Muscle Viscoelasticity But Did Not Affect Maximal Voluntary Contractions in Footballers. The Journal of Strength & Conditioning Research, 28(11). Retrieved from https://journals.lww.com/nsca-jscr/Fulltext/2014/11000/Acute_Static_Vibration_Induced_Stretching_Enhanced.12.aspx
Kruse, N. T., Silette, C. R., & Scheuermann, B. W. (2016). Influence of passive stretch on muscle blood flow, oxygenation and central cardiovascular responses in healthy young males. American Journal of Physiology. Heart and Circulatory Physiology, 310(9), H1210-21. https://doi.org/10.1152/ajpheart.00732.2015
Kubo, K., Kanehisa, H., Kawakami, Y., & Fukunaga, T. (2001). Influence of static stretching on viscoelastic properties of human tendon structures in vivo. Journal of Applied Physiology (Bethesda, Md. : 1985), 90(2), 520–527. https://doi.org/10.1152/jappl.2001.90.2.520
Little, Thomas & Williams, Alun. (2006). Effects of Differential Stretching Protocols During Warm-Ups on High- Speed Motor Capacities in Professional Soccer Players. Journal of strength and conditioning research / National Strength & Conditioning Association. 20. 203-7. 10.1519/R-16944.1.
Magnusson, S. P., Simonsen, E. B., Aagaard, P., Sørensen, H., & Kjaer, M. (1996). A mechanism for altered flexibility in human skeletal muscle. The Journal of Physiology, 497 ( Pt 1(Pt 1), 291–298. https://doi.org/10.1113/jphysiol.1996.sp021768
Oranchuk, D. J., Storey, A. G., Nelson, A. R., & Cronin, J. B. (2019). Isometric training and long-term adaptations: Effects of muscle length, intensity, and intent: A systematic review. Scandinavian Journal of Medicine & Science in Sports, 29(4), 484–503. https://doi.org/10.1111/sms.13375
Tak, I., Engelaar, L., Gouttebarge, V., Barendrecht, M., van den Heuvel, S., Kerkhoffs, G., … Weir, A. (2017). Is lower hip range of motion a risk factor for groin pain in athletes? A systematic review with clinical applications. British Journal of Sports Medicine, 51(22), 1611–1621. https://doi.org/10.1136/bjsports-2016-096619
Taylor, K.-L., Sheppard, J. M., Lee, H., & Plummer, N. (2009). Negative effect of static stretching restored when combined with a sport specific warm-up component. Journal of Science and Medicine in Sport, 12(6), 657–661. https://doi.org/10.1016/j.jsams.2008.04.004
Wiewelhove, T., Döweling, A., Schneider, C., Hottenrott, L., Meyer, T., Kellmann, M., … Ferrauti, A. (2019). A meta-analysis of the effects of foam rolling on performance and recovery. Frontiers in Physiology, 10(APR), 1–15. https://doi.org/10.3389/fphys.2019.00376
Wilke, J., Müller, A.-L., Giesche, F., Power, G., Ahmedi, H., & Behm, D. G. (2019). Acute Effects of Foam Rolling on Range of Motion in Healthy Adults: A Systematic Review with Multilevel Meta-analysis. Sports Medicine (Auckland, N.Z.), (0123456789). https://doi.org/10.1007/s40279-019-01205-7
Authors: Micael Moreira , Lucas Brink Carvalho