Outsourced Administrative & Secretarial Services

Physical discipline has always been the major focus of training in the exercise and sport world, but more recently, research has turned its eye to the mind as a tool that may facilitate the ability to overcome physical limitations and help performance.  Coaches and others both within and outside of the exercise arena have often acknowledged the importance of the mental discipline of imagery or visualization as a major factor in improving performance, whether it is in sport and exercise, business or physical rehabilitation.

Imagery is a mental discipline tool that is sometimes used to improve performance and technique, facilitate focus and motivation, to alter arousal and anxiety, to rehearse various situations and even to facilitate healing for the injured or infirmed.   Imagery, visualization, mental rehearsal, etc. refer to “creating or recreating an experience in the mind” (Weinberg & Gould, 2007, pg. 296).  Some see Imagery as nonsense, but it is widely known that many elite athletes have incorporated its use into their training with the hope that it will help them perform at their best.  Perhaps less known, is the fact that imagery is now being adopted in physical therapy practice.

The purpose of this paper is to review a small portion of the available literature in order to consider the physical effectiveness of imagery on sport and exercise performance and rehabilitation.  We’ll look at some research which shows the effectiveness of Imagery for healthy individuals, athletes and patients while considering which methods, if any, have been shown to be most useful in producing the most dramatic results.

Muscle Strength Increase in Healthy Individuals

Does imagery measurably improve muscle strength in healthy individuals?   A study was performed to explore whether the practice of Motor Imaging (mental practice without physical practice) is effective in increasing strength of ankle dorsiflexor muscles in healthy individuals (Sidaway, Trzaska, 2005).

24 subjects were randomly divided up equally into three groups of 8 subjects:  a physical practice group, a mental practice group and a control group.  Using a dynamometer, the subjects’ maximal torque production in their ankle dorsiflexor muscles were tested both before and after the test period.  The physical practice group was asked to perform “3 sets of 10 reps of maximal isometric exercises 3 times a week for 4 weeks”.  The mental practice group was asked to perform the same exercise mentally (without physical practice) by listening to an imagery script while attached to the dynamometer to insure no torque was being produced in the target muscle groups during mental practice.  After the 4 week test period was over, the data was analyzed to compare the average change in peak torque production in all three groups.

The physical-only practice group achieved a 25.28% increase in muscle strength in the dorsiflexor muscles.  Significantly, the mental-only practice group achieved a 17.13% increase in muscle strength in those muscles, while the control group experienced an insignificant decrease of 1.77%.  In this study, Imagery, without mental practice clearly showed increases in muscle strength.

Increased performance in athletes

Given the above, is it really possible for imagery to measurably increase actual performance in athletes?  If so, what are the optimal conditions that would create the most significant improvements?  To investigate these questions, a study was performed on novice hockey players (Collins, Devonport, Holmes, Smith & Whitemore, 2001), to explore the effectiveness of two different types of imagery on performance: specifically stimulus-only imagery, versus stimulus imagery combined with response imagery.  Stimulus imagery is defined as imagery which only includes the descriptive elements of the environment, without the physiological responses related to the act that is visualized.  Response imagery includes the elements of the individual’s physiological response, such as elevated heart rate, sweaty palms, cold or warm feelings on skin, feeling of body movements and muscle contractions, etc.

The authors noted that many studies had typically shown the positive effects of imagery by showing an increase in performance for imagery groups as compared to control groups, with physical practice groups performing better than imagery groups.  In studying the effects of imagery on patients with anxiety disorders, (Lang, 1985) it was shown that using response imagery can lead to physiological responses which can strengthen the motor program associated with a specific task.  Other studies have shown increased physiological responses in subjects using response-type imagery as well; hence, the authors of this study hypothesized that images which include a “response” element would be even more effective in improving sport performance than those including only a “stimulus” element.

A group of 27 undergraduates (20 female, 7 male) who had never performed the hockey penalty flick or had any previous training in imagery were collected.  The participants were randomly placed in 3 mixed-sex groups.  Each participant was asked to take 5 practice shots, followed by a pre-test of 20 penalty flicks into a field hockey goal.  Points were given according to their performance (where the shot landed and whether it left the ground).

After the pre-test, the stimulus-only imagery group members were each given the same stimulus imagery script which simply described the scene (such as the sight of the hockey stick, ball, goal and surrounding sounds).   Each member of the response-stimulus imagery group was given their own unique script which reflected their own stimulus plus response experience.

Each imaging group participant practiced their imagery scripts of 20 penalty flicks three times a week for seven weeks.  The control group was instructed not to practice or imagine performing the penalty flick at all during the experimental period.  All three groups received the same amount of attention from the experimental team, with the control group given time learning general information about hockey (in lieu of instructions on imagery or physical practice).

After the test period, the control group results showed only a .5% improvement in scores (only 3 participants improved).  The stimulus imagery group experienced a 31.1% improvement, with the stimulus-response imagery group experiencing a 47.4% improvement in scores.  The results for both imagery interventions were significant, with the stimulus-response imagery group improvement much higher than the stimulus-only imagery group.

Imagery and Spinal Improvement/Pain Reduction

So far, we’ve seen the effects of Imagery on healthy individuals and athletes, but are there applications for the infirmed?  A study was performed (Fairweather & Sidaway, 1993) to investigate the effectiveness of ideokinetic imagery (visualization accompanied by kinesthetic cues) in treating back pain and excessive curvature of the lower spine (lordosis).  It was hypothesized that with frequent practice, ideokinetic imagery would produce improvement in lordosis, kyphosis (excessive curvature of the upper spine) and spinal pain in both males and females.  They also predicted that the relaxation position alone, without ideokinetic imagery, would not produce the same improvement.

The first experiment consisted of 15, 17-year-old male high school student volunteers who were experiencing low back pain during or after exercise, who were also reporting sleep disturbances due to back issues.  The students were told they were going to receive instruction in activity to “improve ease of movement” in their sport.  The subjects were photographed in swim suits, with their spine curvature measured on a grid, rated and graphed.  They were then randomly divided into three groups:  Ideokinetic Imagery, Flexibility/Abdominal Exercise & Control.

The imagery group met 3 times a week for 3 weeks and was given kinesthetic exercises (to increase imagery awareness only) as well as relaxation, and ideokinetic script practice.  The flex/exercise group was given specific flexibility and abdominal strengthening exercises 3 times a week for 3 weeks, while the control group met during those times, but received only the same physical education classes as the experimental group.

The only change/improvement was found in the ideokinetic group, with significant improvements in the mean spinal angle, as well as lordosis and kyphosis angles.  The subjects also reported that though their pain increased during the first week, it completely ceased after that time, whereas the flexibility subjects reported an immediate relief from pain following exercise, but that it returned soon afterward.  The control group had no change in angles or awareness of change in back pain.

A second experiment was conducted to adjust for an addition of females, and investigated the possibility that relaxation alone may have accounted for the improvement.  40 undergraduate student volunteers (half male, half female), aged 18-23 were taken from physical activity classes.  They were not told this had anything to do with posture, but with gait.  Rather than taking photographs, the subjects were videotaped and asked to walk.  Their standing posture was evaluated, measured and noted.  They were divided evenly into the same groups as the first experiment, and instructed to do the same things, but a 4th group was added.  This group was similar to the ideokinetic group, but was only directed in deep relaxation exercises for those 15 minute sessions, without the ideokinetic imagery.  These experiments were conducted 3 times a week for 15 minutes over an 8 week period.

This time, the only significant result was found in the male ideokinetic imagery group, both in pain relief and spinal angles.  Subjects with the most pain and worst lordosis reported a complete cessation of back pain.  Interestingly, there was no significant improvement for females.

This study suggests a need to further investigate the helpfulness of ideokinetic imagery in females, but seems to show conclusively that, for males, it is more effective than simple relaxation or flexibility/strength training for back pain resulting from acute lordosis or kyphosis.

Conclusion

The ankle dorsiflexion study was done only with healthy individuals, so we do not know definitively what the implications would be for the infirmed/injured.  The study was also only applied for 4 weeks, during the time when neural adaptations would be occurring in both the physical and mental groups.  If the sample had been taken over a longer duration, the differences between the 2 groups may have been expected to be much larger, since adaptations would have occurred in the physical practice group that may not have been expected in the mental practice group.

Even so, since it is possible to see such significant strength gain in people who are using mental imagery only, it seems a logical conclusion that imagery may be helpful in rehabilitation programs to facilitate the neurological adaptations needed before actual strength training (even in the form of isometrics) can be applied to injured athletes or other patients with neurological or musculoskeletal injuries.  It also seems a legitimate adjunct to any sport and exercise program for healthy individuals.

With regard to the use of Imagery in sport, and in particular, evaluating the effectiveness of different types of imagery, the implications of the penalty flick study seem to be significant, since it is widely held that novices experience a smaller improvement with imagery than experienced athletes.  If stimulus-only imagery can improve scores by almost 30% and stimulus-response imagery by almost 50% in novices without physical practice, it seems stimulus-response imagery training could be a very effective way to improve performance in athletes during physical rest phases, in between practices or during injury recovery periods.  Also worth noting is the use of a personalized script for the more successful group.  Was the success of this second group partially due to using a more meaningful and personally-tailored script?

As far as considering imagery limitations, pain relief and even musculoskeletal changes, the lordosis/kyphosis study is even more intriguing.  Why would there be an improvement in males rather than females?  Could it be that the males in this particular study seemed to have the greatest spinal angle issues; since it was emphasized that the participants with the greatest lordosis benefited the most?  Could this be related to the cause of the spinal angle issues, or the imagery ability of the males vs. the females?   Could the differences between males and females be attributed to the type of imagery used?  It would be interesting to repeat the first study with females experiencing back pain resulting specifically from acute spinal angle issues, or experiment with different types of scripts/visuals with females.  Also worth consideration and further study are the types of flexibility exercises used.

This review of literature was fascinating for me, because I expected that visualization would change one’s “mindgame” (confidence level, focus, technique, etc.) but I did not expect to see actual physical change take place with mental imagery only.  Now I wonder about the practical applications of Imagery and would be interested in learning more about the different types of imagery and their uses, in sport, physical therapy… even business, psychotherapy and medicine.  The art and science of disciplining one’s mind has much greater applications than I think most of us realize.

References

Collins, D., Devonport, T., Holmes, P., & Smith, D. (Dec 2001). The effect of theoretically-based imagery scripts on field hockey performance. Journal of Sport Behavior, p408, 12. Retrieved November 20, 2007 from Gale Expanded Academic ASAP.

Fairweather, M.M. & Sidaway, B. (Dec 1993). Ideokinetic imagery as a postural development technique. Research Quarterly for Exercise and Sport 64.n4. Retrieved November 23, 2007 from Gale Expanded Academic ASAP.

Lang, P.J. (1985).  The cognitive psychophysiology of emotion: Fear and anxiety. In A.H. Tuma and J.D. Maser (Eds.), Anxiety and the anxiety disorders, pp 131-170. Hillsdale, NJ: Lawrence Eribaum

Sidaway, B. & Trzaska, A. R. (Oct 2005). Can Mental Practice Increase Ankle Dorsiflexor Torque? Physical Therapy. Vol 85, Iss10. Retrieved November 20, 2007 from Proquest Research Library.

Weinberg & Gould. (2007). Foundations of Sport and Exercise Psychology—4th ed. Champaign, IL: Human Kinetics.

Copyright Susan Puetz Turnquist, NASM-CPT, AFAA-CGT, 2008

Introduction:

In recent decades past, it has often been accepted that aging means lowered quality of life because of injury, disease and reduced cardiovascular endurance and strength.  The accepted norm was to taper off on activity and accept the inevitable decline in health and athletic involvement after age forty.  Runners are often told to quit running because it is “hard on the body”.  As one approaches middle age, and sees a decline in athletic ability as compared to a much younger population, the question arises:  Is it healthy to continue training hard into old age?  There is a plethora of research involving the benefits of endurance training in aging gracefully. This paper will discuss studies which address the benefits of long term endurance training for the aging population on their immune systems, cardiovascular systems and exercise capacity.

Immune Function, Endocrine Function and VO2 Max Study

One major concern for the aging is the inevitable reduction in immune system health, leading to an increased risk of infection followed by high rates of disease, lowered quality of life and eventual death.  It has been hypothesized that exercise may slow the rate of deterioration of the immune system.

Researchers, seeking to investigate the effects of exercise on the immune and endocrine systems, compared elderly male runners to normal sedentary elderly and young men (Arai, M. et al, 2006).  A group of 20 recreational runners (aged 61-80); a group of healthy sedentary controls (aged 60-75) and 10 young healthy sedentary controls (aged 23-34) were studied.  The sedentary groups had not been involved in any physical activity for more than 15 minutes 3 times a week for at least 2 years prior to the study.  The group of runners ran an average of 38.7 miles per week for 21 to 25 years. 

When tested to exhaustion on a treadmill according to Bruce protocol, the elderly runners presented a 52% higher VO2 max (maximum oxygen consumption) than the elderly sedentary subjects – showing similar results as the young sedentary subjects.   High VO2 Max is an indicator of fitness and represents the amount of oxygen the body can utilize in one minute at maximum capacity.

It was determined in advance that the cytokine profile would be an accurate way to measure immune system health, so blood was tested using careful protocol.  Cytokines are proteins released by cells and include interleukins (IL) which generate an immune response when necessary.  A high level of serum IL-2 is known to be associated with healthier immune system response and was found to be at a much higher level in elderly runners than their peers – at a similar level to that of the young men.  Low levels of serum IL-6 were found in the elderly runners as compared to their peers.  Low levels of this serum have been hypothesized to be a marker of health in aging.  IL-3 in the elderly runners was found to be at a similar level to that of the young men, suggesting that training over a long period of time may counteract the effects of aging on this interleukin.  All other blood levels tested did not show any significant difference from their elderly peers.  Hormones in this age group did not seem to be affected by exercise.

Heart rate variability and exercise capacity in elderly master athletes study

As humans age, exercise capacity and heart rate variability (HRV) decline.  The effect is a lowered ability to carry out strenuous tasks, and a higher rate of heart issues and possibly earlier death.  Researchers in Italy investigated the effect of long term, chronic endurance training on HRV and exercise capacity (Galetta, F., et al, 2005)

20 healthy male veteran runners with an average age of 68.5 (+-4 years) were studied and compared to 20 healthy sedentary men of the same age.  The runners had been practicing endurance running for at least 40 years, training 1-2 hours for 5 days each week, including long distance 3 days and walk-weight training for 2 days.  They also raced 5-10k each week or 20 k every 2 weeks.  The athletes with higher than 55 VO2 max and sedentary individuals with lower than 45 VO2 max were selected.  This parameter may have affected the results.

HRV was examined using 24 hour Holier monitoring and then analyzed by computer.  Exercise capacity was measured using a ramptype progressive exercise test on a cycle ergometer to the tolerance limit.  The ergometer was equipped with a computer which regulated exercise intensity while they maintained a cadence of 60 revolutions per minute after warm-up. 

The two groups were similar in Body Mass Index (BMI), total cholesterol and glucose values, but the athletes showed lower blood pressure and resting heart rate, increased HDL (the healthy form of cholesterol) and decreased LDL cholesterol (the unhealthy form of cholesterol).  HRV measures were significantly higher in the athletes compared to the sedentary controls.  Lower HRV measures and exercise capacity are known to predict higher mortality rates and cardiac issues.  Exercise capacity was shown to be significantly higher in the athletes.  The heart rate rhythm in the sedentary men was blunted while it was preserved in the athletes.    Athletes were able to work at a much higher load at peak heart rate than the sedentary controls.  The researchers concluded that the decline of HRV which is normally associated with age may be partially due to lifestyle.  However, they affirm that athletes may have a genetic predisposition and that there may be other variables that may affect the results.

Comparisons between Athletes and Former Athletes (Nessel, 2004)

Normal losses in VO2 max in non exercisers run an average of 1% per year in normally active men after age 35, showing a reduced ability for the body to use oxygen during aerobic activity.  According to a review of literature (Nessel, 2004), one study showed that runners who stopped training during middle age actually had a loss of 43% from the ages of 23-53 while another study showed runners and rowers who had continued training at a high level experienced only a 5-6% decline per decade (and sometimes as low as 1-2% per decade). 

He also reports that “endurance training decreases the loss of elasticity from the lungs and chest wall,” so he believes losses in VO2 max are caused by slowed transport of oxygen to muscles rather than decreased respiratory ability.  “It appears that high intensity training has a slowing effect on the rate of loss in aerobic capacity during the early and middle years of adult life (30-50 years of age), but less effect after age 50” (Nessel, 2004).  However, Nessel also notes that cardiovascular improvements resulting from training for the older individual are similar to those obtained by a younger person.  

Osteoarthritis in the Lower Extremities

So the typical question remains: is running healthy for athletes’ joints?  Many runners quit because of fear of osteoarthritis (OA) in the lower extremities, and those who do not quit, are often chastised by friends and relatives.  Though research is still needed on this subject, the consensus seems to be that high impact, repetitive sports do result in injury, which seems to be a high risk factor in developing OA, but that running in itself does not present a problem for this particular disease (Conaghan, 2002).   In fact, according to Runners World, a 14 year longitudinal study compared runners who ran an average of 26 miles per week to those who ran 2 miles per week.  The runners were found to have “25% less musculoskeletal pain” than the controls (Burfoot, 2006).  The hypothesized reasons for reduced pain are increased stability and strength of the muscles and tissues surrounding the joints of a well trained athlete. 

Another possible factor in joint health may be attributable to a reduction in excess body fat in seasoned runners.  In an article in Runners World, Ketteler (2007) reports that “sedentary, overweight people are 45% more likely to develop OA than those who are active”.  She interviews Dr. Patience White, M.D., of the Arthritis Foundation, who believes excess weight produces pressure on the joints and “seems to accelerate the breakdown of cartilage”.  Older endurance athletes (age 45) have a reported average body fat of 11% for men and 18% for women compared to sedentary averages of 19% and 26% (Nessel, 2004).

Conclusion

VO2max gains through exercise while young are obviously not retained when training ceases.  At the same time, losses that are inevitable with aging are kept minimal only through continuous, vigorous training.   There appears to be no need to cut back on training intensity as long as one is medically able, and as long as one “listens to the body” when there may be risk of joint injury leading to increased risk of OA.  In fact, cutting back will result in losing all that one has gained through sometimes years of training.  Continuing at a comfortably high intensity will considerably reduce the losses to cardiovascular and immune system health. 

Though it is impossible to prevent the inevitable when it comes to aging, it is certainly possible to maintain a high quality of life and increased life expectancy.  Running, as well as other endurance training appears to be a viable and low risk way to accomplish this, in tandem with proper diet and strength training.  When taking all the benefits of running into consideration and weighing them with any possible risks, it is difficult not to conclude that continuing to run at a high level would allow one to expect the longest, healthiest, most pain-free life genetically possible.

References:

Anderson, O. (1998, August). Defeat father time. Runner’s World, 33(8), 34.  Retrieved March 21, 2008, from Research Library database. (Document ID: 31701520).

Arai, M. H., Duarte, A J, & Natale, V. M. (Dec 2006). The effects of long-term endurance training on the immune and endocrine systems of elderly men: the role of cytokines and anabolic hormones. Immunity & Ageing, 3, p.NA. Retrieved April 21, 2008, from Health Reference Center Academic via Gale.

Burfoot, A. (Feb 2006). Does running cause arthritis?. Runner’s World, 41, 2. p.55. Retrieved May 14, 2008, from Health Reference Center Academic via Gale: http://0-find.galegroup.com.alice.dvc.edu:80/itx/start.do?prodId=HRCA

Conaghan, P G (2002). Update on osteoarthritis part 1: Current concepts and the relation to exercise. British Journal of Sports Medicine, 36(5), 330-3.  Retrieved May 14, 2008, from ProQuest Health and Medical Complete database. (Document ID: 222988831).

Galetta, F., et al. (2005). Lifelong physical training prevents the age-related impairment of heart rate variability and exercise capacity in elderly people. Journal of Sports Medicine and Physical Fitness, 45(2), 217-21.  Retrieved March 21, 2008, from ProQuest Health and Medical Complete database. (Document ID: 920579341).

Ketteler, J. (10/25/07). The benefits of running. Runner’s World. Retrieved May 14, 2008, from Runners World website http://www.runnersworld.com/article/0,7120,s6-241-285–12232-0,00.html.

Nessel, E H (Summer 2004). The physiology of aging as it relates to sports. AMAA Journal, 17, 2. p.12(6). Retrieved March 21, 2008, from Expanded Academic ASAP via Gale.

Copyright Susan Puetz Turnquist, NASM-CPT, AFAA-CGT, 2008