An update on life and thoughts on stiff upper backs

055F337F-1859-4789-9A6B-C21C41B26486Hello and good evening/afternoon/morning to those of you who still follow my blog (although it’s been dormant for a while) and to those who perchance have happened upon my writings.

 

Between my recent readings which have included Tribes (Seth Godin) and The War of Art (Steven Pressfield), maturation in my work as a strength and conditioning coach, and recent entrance into the gauntlet of fire that is the first term of my DPT (doctorate of physical therapy) program, I’ve felt a calling to write more. If I want professional writing to be a part of my career, I’ve come to the realization that I should approach writing as a regular endeavor rather than “waiting” for the perfect inspiration to strike. Here it goes.

My aim of today’s post, and the others to come, is to share:

  • my journey in education and life
  • my raw opinions, thoughts, and unanswered questions on topics relating to physical therapy, movement, mindset, nutrition, and training
  • some insights and tips I think could benefit other practitioners, athletes, and everyday folks in the realms of physical, mental, and emotional self-care

I go through phases of curiosity over different areas of the body and pathological movement patterns I see around me. As of late, upper back “tightness”  (specifically in the region of the top three or four vertebral segments of the thoracic spine) has been on my radar (although, I really dislike the use of the word “tight” as a qualification due to its ambiguity but at this point, I don’t know a better alternative), and I’ve been seeing needs to remedy it everywhere. My mom who is a runner swings her arms from her glenohumeral joints while her scaps and upper back remain fixed and the other day, woke up at 4:30am up with a non-traumatic spasm in her upper back and neck that was so bad she was nauseous and couldn’t move for hours. My dad and two of my training clients, all of whom spend long hours seated at computers, lack rotation in those upper thoracic segments and have recently developed anterior/middle shoulder aching and pinching sensations in the proximal regions of their shoulders. I, personally, have also worked around my own cervicogenic “tension” headaches that occur from workouts or during times of stress (read: sitting in school or studying for long hours) for the last couple of years, and I believe a stiff upper back to be a contributor.

download.jpg

The cluster of associated signs includes some degree of an anterior head carriage, tight upper traps/pec minor/levators/scalenes/SCMs SCOMs, and/or internally rotated shoulders (yes, I’m pretty much describing upper cross syndrome). Really, who doesn’t have some degree of UXS nowadays?  With such prevalence, I think it’s important for me, as a practitioner, to learn how to address it, but I get frustrated because I haven’t figured it out yet (and I don’t think that many practitioners have either). I’m constantly running into sticking points with myself and my clients, and I think that sticking points arise when a prescribed intervention addresses a symptom of a problem rather than the root cause or only part of a more complex root cause. For example, massaging an individual’s tight levator might provide temporary relief, but without addressing the reason that muscle is tight, it will undoubtedly get tight again. Performing a thoracic spine mobilizing intervention (i.e., spinal manipulation, “open the book,” “thread the needle,” etc.) may be a good step in the process of alleviating upper back issues but if the root cause is related to suboptimal respiration mechanics (for example, excessive use of accessory musculature), the 20,000 breaths an individual takes in a day utilizing those dysfunctional mechanics are going to quickly revert any progress made until addressed.

As I type these thoughts, the conclusion I’ve arrived at for today (and it may be different tomorrow) is that the best way to address upper back “tightness” is

1) to learn how to differentially assess each of these areas, including breathing, soft tissue quality, strength/capacity of affected musculature (MMT), mobility, and mechanics in a way that helps identify weak/dysfunctional links and address those specifically.

17438931_401779633517737_2669084551103381504_n

and

2) continue learning and refer to other practitioners when problems arise that are out of your scope

As a final thought, any interventions/treatments done only once will not completely solve problems that have occurred over many days/months/years. Consistency with an intervention over a period of time is the only way to create and enforce the desired adaptations.

What are your thoughts on this topic? How do you assess and approach it? Do you run into sticking points with your clients/self?

Yours in Movement,

K8

Advertisements

Type 3 Diabetes, Growing body of evidence

normal-vs-alzheimers-brain

There is a recent emergence in scientific research regarding an association between insulin and Alzheimer’s disease: it has been termed Type 3 Diabetes (Ahmed, Mahmood, & Zahid, 2015). Alzheimer’s disease is a progressive neurodegenerative disorder that is age-related and characterized by intracellular neurofibrillary tangles (NFT) and amyloid-beta plaques. Common findings in the brains of afflicted individuals show impairments of energy metabolism and glucose utilization, as well as insulin receptor, insulin, and IGF deficiency (Ahmed et al., 2015).

brain-w550

Insulin plays a role in regulating energy homeostasis in the hypothalamus, and insulin receptors are widely distributed throughout the brain, especially in the hippocampus, amygdala, and septum (Ahmed et al., 2015). The hippocampus, of note, regulates acquisition and consolidation of memory, and there may be a role of insulin in potentiating memory. Non-diabetic Alzheimer’s patients have manifested increased levels of peripheral insulin resistance biomarkers in their hippocampi. A potential mechanism suggested is that progressive insulin resistance in the brain may increase expression of cerebral inflammatory mediators leading to oxidative stress and mitochondrial dysfunction and a self-propagating cycle of neurotoxicity from oxidative stress and amyloid-beta deposits.

Growing evidence associating Alzheimer’s disease with insulin resistance further highlights the importance of maintaining a healthy body weight and not consuming excessive amounts of sugars and fats in our diets.

To learn more about insulin check out my article: Be More Sensitive…To Insulin!

Reference

Ahmed, S., Mahmood, Z., & Zahid, S. (2015). Linking insulin with Alzheimer’s disease: Emergence as type III diabetes. Neurological Sciences, 36, 1763-1769.

Your ability to sit on the floor and get back up is more important than you may think!

Getting to the ground and back up is a fairly complicated motor skill which can vary in difficulty based on one’s surroundings and physical limitations. There are many ways to accomplish this task involving movements such as squatting, lunging, kneeling, or bending over, and it requires lower body mobility, strength, and stability as well as a certain amount of comfort being on the floor. Not only is one’s ability to get to the floor and back up an important predictor of mortality, but it is also crucial for many activities of daily life as well as for recovery in the event of a fall (de Brito et al., 2012; Wang et al., 2016). Fall risk is a great concern, especially in older adults due to the injuries, disability, and reduction in quality of life that a fall can cause. Many studies have reported that reduced muscle strength in the lower extremities raises the risk of failing (Wang, D. et al., 2016).

Sit-and-Stand-test.jpg

A study by de Brito et al. (2012) scored 2,002 adults ages 51 to 80 years old on their ability to sit down on the floor and get back up. They were scored out of 10 possible points and deductions were made for the use of another body part or the floor for support while getting down or back up. The researchers followed up with the individuals over the next six years, and 159 of the participants died. Every point increase in a person’s test score correlated with a 21% reduction in his or her risk of death in the next six years. While this is a correlation study and evidence of correlation isn’t evidence of causation, the association between movement ability and mortality is hard to ignore.

Try it out now. Start by standing up. Sit down on the floor using your hands or other objects as little as possible. Every time you use something for assistance, subtract one point from five. Stand up from the floor using as little help from hands and objects as possible. Subtract one point from five each time you use hands or objects for assistance. Add your results from getting down (a number out of 5) and getting up (a number out of 5) for your score out of 10. Each point less than 10 increases the probability of death in the next six years by 21%. Are you ok with your score? Keep reading to learn how to improve!

If getting down to the floor and/or up is nearly impossible for you: 

Here are three simple exercise progressions you can work through over the next 6-8 weeks.

  1. Sit to stand
  2. Lowering and raising in a split stance (similar to a lunge)
  3. Step ups

Sit to stand

Select a box or chair that is a comfortable height. Sit down to it and stand back up without using your hands or assistance. Progress to tapping your butt on the box instead of entirely transferring your weight onto it, and gradually lower the box to increase the distance you raise and lower yourself. This increases comfort with getting down to and up from progressively lower seats and strengthens the leg muscles necessary to do so. If you progress to the point where you can lower and raise yourself to a point at more than 90-degrees of knee flexion, progress this exercise to include lying down. In this variation, sit/squat down to the low position, transfer all your weight to the box, and lie all the way down. To reverse the movement, sit up from lying supine and squat up from that position.

4067082_orig

Lowering and raising in a split stance

Slightly lower and raise your body (bending the front and back knees) in a split stance position using TRX straps for support. With practice, increase the distance you lower and raises your body, and then decrease the amount of assistance used to stabilize from two TRX straps to one strap to no assistance. This exercise increases comfort and stability in the split stance position one uses to get up from the ground, and it strengthens the leg muscles which are important for the movement.

trxbacklunge

Step ups

Step up to a small platform using one leg. Similar to the other exercises, this will increase leg strength, stability in a single leg stance, and comfort in a movement pattern one can use to get up from the ground. Progress by increasing the repetitions of step ups performed on each leg and the height of the platform you are stepping up to.

step-up.jpg

The next step:

Once you can get down to the ground and back up with relative ease, I’d suggest including a Fall Matrix in your workout warm-up once a week.

  1. Start standing. Place one hand on your same-side knee. Lay down, with your back against the floor and stand back up without removing the hand from your knee. Then lay down with your stomach on the floor without removing the hand from your knee, and stand back up. Optional: Lay down with your right side on the floor, and stand back up. Then repeat on the left side.
  2. Repeat these 4 variations touching the other side’s hand to its same-side knee.
  3. Repeat these 4 variations touching one hand to the opposite side knee.
  4. Repeat these 4 variations touching the other side’s hand to its opposite side knee.

Progress these exercises by touching your hand to a body part lower than the knee, for example, place your hand below the knee, on your shin, on your ankle, on your toes.

Like many things with our bodies, if you don’t use it, you lose it. Get on the ground and back up regularly so you don’t lose your ability to!

References
de Brito, L. B., Ricardo, D. R., de Araujo, D. S., Ramos, P. S., Myers, J., & de Araujo, C. G. (2012). Ability to sit and rise from the ground as a predictor of all-cause mortality. European Journal of Preventive Cardiology. doi: 10.1177/2047487312471759
Wang, D., Zhang, J., Sun, Y., Zhu, W., Tian, S., & Liu, Y. (2016). Evaluating the fall risk among elderly population by choice step reaction test. Clinical Interventions in Aging, 11, 1075-1082. doi: 10.2147/CIA.S106606

Internal vs External Attentional Focus? It depends…

Verbal instructions given to individuals who are learning motor tasks have two types of attentional focuses, externally-focused and internally focused cues. Instructions with an external focus of attention refer to the effects of body movements instead of the movements themselves while internally focused cues directly address the movement of the body or specific body parts (Poolton, Maxwell, Masters, & Raab, 2005). Sam Leahey has good examples of internal and external cues for various exercises and movements in this article.  Whether the use of externally-focused versus internally-focused cues is more efficacious in the learning of motor tasks is controversial in the research.

screen-shot-2016-09-08-at-11-26-22-am

Like many topics in Kinesiology, I believe the answer to which attentional focus is better, internal or external, is it depends. What is the purpose of performing the targeted skill? If one is performing a squat, is he or she trying to move better, increase aesthetics (i.e., muscle size), or achieve a weightlifting PR? If a client is doing squats to move better, internal cues may be more effective for optimizing positioning of the knees, feet, and chest. In clients with aesthetic goals, the aim of squatting may be to increase gluteus hypertrophy. Research performed by Calatayud et al. (2016) demonstrated that an internal focus of attention on using certain muscles while performing a bench press increased muscle activity in the specific muscles on loads under 80% of 1RM. Lastly, when the goal of squatting is maximal strength, an external attentional focus is likely to result in better performance according to a study by Halperin, Williams, Martin, and Chapman (2015). They observed that participants with external focuses of attention exerted 9% more force on an isometric mid-thigh pulling exercise compared to participants with internal focuses.

In many studies, performance outcome measures are used to demonstrate the effectiveness of external attentional focus. In research by Wulf, Gartner, McConnel, and Schwarz (2002) task success is measured by how accurately participants hit target areas. The study by Poolton et al. (2005) judged success from accuracy on the putting task. Not all sports training and fitness activities have these kinds of outcome-based goals. Many who weightlift can display impressive amounts of strength despite under-recruiting certain muscles like the gluteal muscles or use of risky techniques. Internal cuing may be warranted to improve recruitment of proper muscles. Volleyball players can focus on jumping faster and higher all day, but if they exhibit knee valgus or other form flaws their success potential is limited and their injury risk is heightened. Internal cues may be necessary to bring a conscious focus back to a pattern that was learned incorrectly.

References

Calatayud, J., Vinstrup, J., Jakobsen, M. D., Sundstrup, E., Brandt, M…Anderson, L. L. (2016). Importance of mind-muscle connection during progressive resistance training. European Journal of Applied Physiology, 116(3): 527-533.

Halperin, I., Williams, K., Martin, D. T., & Chapman, D. W. (2015). The effects of attentional focusing instructions on force production during the isometric mid-thigh pull. Journal of Strength & Conditioning Research, DOI: 10.1519/JSC.0000000000001194

Poolton, J. M., Maxwell, J. P., Masters, R. S., & Raab, M. (2005). Benefits of an external focus of attention: Common coding or conscious processing? Journal of Sports Sciences, 24(1): 89-99.

Motivation

Intrinsic motivation describes one’s internal drive to participate, exert effort, and be persistent when engaging in an activity. Intrinsically motivated individuals partake in an activity simply due to the pleasure and satisfaction derived from the activity itself (Hunter, 2008).  Not surprising, it is a huge factor in long-term exercise program adherence. As a person who takes on clients working toward specific fitness goals, it is part of my job to keep them committed to their goals so they are successful. Cultivating a client’s intrinsic motivation is an important part of this.

Hunter (2008) identifies three facets of intrinsic motivation: autonomy, competence, and relatedness. Autonomy means that a client has some control over his or her workout. One way I like to give clients autonomy is by letting them choose the weight they want to lift during exercises, within my parameters (i.e., they can lift the weight with good technique, they are not risking injury, the weight corresponds to my desired intensity, etc.). I also ask clients or the kids in my group classes for feedback on exercises. For example, I’ll ask the kids if any of the exercises are too easy or too hard, or which exercise is their favorite or least favorite of the exercises in a circuit. These choices involve my clients in the decision-making aspects of their workouts while keeping them on track to meet their goals.

Competence describes a client’s belief in his or her ability to perform a task. Hunter (2008) suggests providing ample opportunities for clients to practice performing quality skills. I start many of my youth strength and conditioning classes with 5-10 minutes of jumping rope, and many kids do not do this well, at first. I provide the beginners with lots of positive feedback and encouragement in their first classes. In just a few weeks of practice, at the start of every class, kids will master the basics of jumping rope. For many, improving so much in such a short time is a big confidence booster.

Relatedness is the third component of intrinsic motivation that refers to an individual’s connection or sense of belongingness to a group (Hunter, 2008). I actually had a shocking moment yesterday when, after teaching my gym’s level 1 strength and conditioning class to two boys of similar size and age, I asked them if they knew each other’s name and neither did! A lot of kids develop relationships with the coaches at the gym, which fosters some relatedness, but I could definitely do more to develop connections between the kids in my classes.

A study by Evans, Cooke, Murray, and Wilson (2014) explored how the temporal proximity of anticipated positive outcomes affected intrinsic motivation. Proximal outcomes were defined as the benefits that occur immediately during or within a few hours of a single exercise bout, whereas distal outcomes occur after days, months or years of consistent physical activity. This study demonstrated that the intrinsic motivation of subjects with lower levels of past physical activity significantly increased when they were exposed to proximal outcomes compared to distal.

As a coach and trainer, I’ve always understood the importance of motivating others (and myself) with the positive benefits of consistent exercise, but my temporal outcome differentiation was between short-term outcomes (in the next month or two) and long-term outcomes (in 6 months to a year). The idea of focusing on immediate outcomes from single workouts is fantastic. I may not be the greatest example because I generally enjoy exercise, but reading through the list of proximal positive outcomes from the study has really motivated me to workout tonight. I may even print it out and post it by my desk. I love the idea of encouraging clients to make lists of proximal positive outcomes or reference the one from this study, and I think it could go a long way in developing intrinsic motivation with exercise.

Screen Shot 2016-08-19 at 7.22.57 PM.png

Previous studies have reported the effect motivational climate has on an athlete. The perception of a mastery motivational climate, emphasizing “learning, effort, improvement, and success determined by self-reference criteria,” has been demonstrated to increase intrinsic motivation (Brinkman-Majewski & Weiss, 2015).  This is opposite of a performance motivational climate, where success is determined in competition to others, leading to increased anxiety and less satisfaction (Brinkman-Majewski & Weiss, 2015). Creating mastery motivational climates with fitness clients could be done as a coach by not comparing clients to each other and highlighting personal PRs and improvements. Especially when working with kids whose sense of self is in a more formative stage, emphasizing task-involved goal orientations could increase the perception of the motivational climate, thereby influencing intrinsic motivation.

References

Brinkman-Majewski, R. E. & Weiss, W. M. (2015). Examination of the motivational climate in the athletic training room. Journal of Sports Behavior, 38(2), 143-160.

Evans, M. B., Cooke, L. M., Murray, R. A., & Wilson, A. E. (2014). The sooner, the better: Exercise outcome proximity and intrinsic motivation. Applied Psychology: Health and Well-being, 6 (3), 347-361. doi:10.1111/aphw.12032

Hunter, S. D. (2008). Promoting intrinsic motivation in clients. Strength and Conditioning Journal, 30(1), 52-54.

Osteoporosis, Age, Parkinson’s decrease dynamic balance and increase fall risk

Motor abilities influence an individual’s success in the performance of certain motor skills (Magill & Anderson, 2013). A motor ability of interest is dynamic balance, or the ability to maintain stability while one is in motion, as there is a strong correlation between poor balance and falls (although it is not the only factor), which are a large health concern among many populations (Ünlüsoy et. al 2011). I have had many clients with various conditions, including age, Parkinson’s disease, and osteoporosis, who were unsteady during locomotion due to poor dynamic balance.

All three of these conditions, age, Parkinson’s disease, and osteoporosis, have a negative influence on the dynamic balance category of motor abilities (Paolucci et. al 2014; Ünlüsoy et. al 2011). Age-dependent change in the musculoskeletal, sensory, and neural systems decrease balance ability in older adults (Maki & Mcllroy, 1996). Parkinson’s disease occurs in the brain’s basal ganglia when there is a lack of dopamine production in the substantia nigra, and it causes bradykinesia, akinesia, tremor, and muscular rigidity (Magill & Anderson, 2013).  Paolucci et al. (2014) state that a “balance disorder is one of the most important impairments” in this population due to statistics showing substantially greater incidence of falls among those with PD (70% of individuals with PD fall once a year and 50% of them fall twice a year in comparison to only 30% of healthy adults over the age of 65 who fall once in a year). Osteoporosis is a bone disease where bones become increasingly fragile from microstructure impairments in the bone tissue and decreases in bone mass. Ünlüsoy et. al (2011) demonstrated that dynamic balance in osteoporotic women was significantly worse than in healthy individuals.

There are many factors influencing one’s ability for dynamic balance during locomotion including muscle strength, interpretation of vestibular and proprioceptive information, and visual feedback (Paolucci et. al 2014). In terms of defining dynamic balance or any type of balance as a motor ability, Magill and Anderson (2013) state balance is a “multidimensional ability that is specific to the task or skill in which balance is involved,” and the specificity of motor abilities hypothesis postulates that individual motor abilities are relatively independent of one another. Given these assumptions, it is challenging to articulate the specific balance ability or abilities influencing locomotion.

If a client or patient came to me requesting help with dynamic balance while walking, I would perform various tests to rule out (or in) factors that may contribute to difficulty walking. I would assess muscular strength and endurance, especially in the lower extremity, observe the patient’s normal walking gait for noticeable abnormalities, and inquire into the patient’s medical history to rule out diseases or conditions, including those previously discussed, that may impact dynamic balance. I would also question the patient about lifestyle factors (i.e., recent accident or trauma, change in medication, etc.) that may be contributing to the deficit. If the patient has good muscle strength in the lower extremity, adequate gait mechanics, and no red flags in his or her medical history, this would indicate a problem with the motor ability of dynamic balance.

Additional ideas of assessments for dynamic balance related to gait were reviewed in a study by Bloem et. al (2016). This study recommended clinical tests including the UPDRS-derived Postural Instability and Gait Difficulty score, Berg Balance Scale, Mini-BESTest, Dynamic Gait Index, Freezing of Gait Questionnaire, Activities-specific Balance Confidence Scale, Falls Efficacy Scale, Survey of Activities, Fear of Falling in the Elderly-Modified, 6-minute and 10-m walk tests, Timed Up-and-Go, and Functional Reach (Bloem et. al, 2016). Further research on my part is needed into these methods, but any would be reliable assessments of dynamic balance.

Motor abilities limit a person’s success in performing a motor skill. In the case discussed, dynamic balance is a motor ability that, if affected, can decrease one’s success at walking without falling. I believe it is important to note that while motor abilities may limit achievement in another skill, motor abilities themselves can be practiced, coached, and improved which would also benefit the motor skill performance. The most important part of treating a motor ability deficit is identifying and distinguishing it from other possible causes of poor motor skill performance.

References

Bloem, B. R., Marinus, J., Almeida, Q., Dibble, L., Nieuwboer, A., Post., B.,…Schrag, A. (2016). Measurement instruments to assess posture, gait, and balance in Parkinson’s disease: Critique and recommendations (abstract only). Movement Disorders. doi:10.1002/mds.26572

Magill, R. A. & Anderson, D. I. (2013). Motor learning and control: Concepts and applications (10th ed.). New York, NY: McGraw Hill.

Maki, B. E. & Mcllroy, W. E. (1996). Postural control in the older adult (abstract only). Clinical Geriatric Medicine, 12(4), 635-58.

Nakano, W., Fukaya, T., Kobayashi, S., & Ohashi, Y. (2016).  Age effects on the control of dynamic balance during step adjustments under temporal constraints. Human Movement Science, 47, 29-37. doi:10.1016/j.humov.2016.01.015

Paolucci, T., Morone, G., Fusco, A., Giuliani, M., Rosati, E., Zangrando, F., & … Iosa, M. (2014). Effects of perceptive rehabilitation on balance control in patients with Parkinson’s disease. Neurorehabilitation, 34(1), 113-120. doi:10.3233/NRE-131024

Ünlüsoy, D., Aydoğ, E., Tuncay, R., Eryksel, R., Ünlüsoy, İ., & Çakcı, A. (2011). Postural Balance in Women with Osteoporosis and Effective Factors. Turkish Journal Of Osteoporosis / Turk Osteoporoz Dergisi, 17(2), 37-43.

Will Power and Healthy Habits

Psychological deterrents to exercise and healthy eating adherence are of great interest to me. We’ve previously discussed that people who are more skillful may be more likely to be active, and self-efficacy research reveals that an individual’s belief in his or her ability to successfully do an activity is a large determinant of if he or she will actually do it (Clarke, 2015; Jongen et al., 2016). Other psychological factors contributing to adherence are support and willpower.

A meta-analysis by Burke, Carron, Eys, Ntoumanis, and Estabrooks (2006) demonstrated the value of contact and/or social support in exercise. The more contact and social support available, the greater the adherence was as well as the beneficial effects of the exercise (Burke et al., 2006). I believe this is the reason activities such as Crossfit and spin classes have such loyal patrons. The group or team dynamics increase members’ consistency and, therefore, their results.

Willpower, synonymous with the concepts of self-control and active volition, is another psychological component of diet and exercise adherence. The Fell article (2011) mentions that willpower is a limited resource that gets depleted throughout the day, therefore, the morning is the best time for one to make the decision to exercise. Baumeister, Bratslavsky, Muraven, and Tice (1998) further demonstrated that one’s willpower is limited and one’s willpower in a certain task (for example, exercise) can be depleted by unrelated acts (such as willpower at work) that share this common resource.

Willpower is important for anyone who is trying to change habits, especially those involving diet or exercise, to understand, as relying solely on will power may not be the most effective method. One of my favorite fitness bloggers, Sohee Lee, writes a lot about how willpower comes into play with diet goals. She discusses how restrained eating (when an individual must resist the urge to eat particular “forbidden” foods) draws more on one’s willpower reserves than unrestrained eating (no food is off-limits), and, often, counter-regulatory eating (overeating “forbidden” foods) results from a period of high restraint (Lee, 2016). Because of this, she recommends a no-food-off-limits approach to healthy eating, and that one should make small changes week by week toward healthier eating as opposed to drastic ones. The less willpower required the more likely the healthy habits will last.

References

Baumeister, R., Bratslavsky, E., Muraven, M., & Tice, D.M. (1998). Ego depletion: Is the active self a limited resource [Abstract]? Journal of Personality and Social Psychology. 74(5):1252-65.

Burke, S. M., Carron, A. V., Eys, M. A., Ntoumanis, N., & Estabrooks, P. A. (2006). Group versus individual approach? A meta-analysis of the effectiveness of interventions to promote physical activity. Sport & Exercise Psychology Review, 2(1), 19-35.

Clark, J. E. (1995). On becoming skillful: Patterns and constraints. Research Quarterly for Exercise and Sport, 66(3), 173-183.

Fell, J. S. (2011, April 4). For best exercise, don’t be lonely or late. Los Angeles Times. Retrieved from http://www.latimes.com/health/la-he-fitness-exercise-adherence-20110404,0,746272.story

Jongen, P. J., Heerings, M., Ruimschotel, R., Hussaarts, A., Duyverman, L., van der Zande, A., & … Visser, L. H. (2016). Intensive social cognitive treatment (can do treatment) with participation of support partners in persons with relapsing remitting Multiple Sclerosis: Observation of improved self-efficacy, quality of life, anxiety and depression 1 year later. BMC Research Notes, 91-8. doi:10.1186/s13104-016-2173-5

Lee, S. (2016) Why can’t I stick to my diet: The what-the-hell effect explained. Sohee Fit. Retrieved from http://www.soheefit.com/what-the-hell/