Music and Physical Performance

As you may be aware, I have a bit of experience with exercise-y type things. However, you don’t have to be an exercise physiologist to realize that music can be utilized as a stimulant and/or sedative. It is widely accepted that music is helpful during workouts, but in this post, we’ll look at some details of why this is the case. Now, let’s get to the science, shall we?

Epinephrine and norepinephrine are the primary hormones synthesized by the adrenal medulla that are associated with the “fight or flight” response. When released, they increase heart rate, increase blood pressure, force constriction of blood vessels, raise respiratory rate, decrease the rate of digestion, increase efficiency of muscle contraction, increase blood sugar level and cellular metabolism. Needless to say, these factors greatly influence physical performance. Here’s a study that associates slow and fast music tempos with the release of epinephrine and norepinephrine, as measured during cycling…

Effects of pre-exercise listening to slow and fast rhythm music on supramaximal cycle performance and selected metabolic variables. Yamamoto T, Ohkuwa T, Itoh H, Kitoh M, Terasawa J, Tsuda T, Kitagawa S, Sato Y. Research Center of Health, Physical Fitness and Sports, Nagoya University, 464-8601, Japan. Arch Physiol Biochem. 2003 Jul;111(3):211-4. http://www.ncbi.nlm.nih.gov/pubmed/14972741

“Listening to slow rhythm music decreases the plasma norepinephrine level, and listening to fast rhythm music increases the plasma epinephrine level. The type of music has no impact on power output during exercise.”

Simple, eh? Forget the pre-workout drink, just make sure you have plenty of fast-tempo songs on your iPod. Here’s another study that supports fast-tempo music for raising the heart rate…

Revisiting the relationship between exercise heart rate and music tempo preference. Karageorghis CI, Jones L, Priest DL, Akers RI, Clarke A, Perry JM, Reddick BT, Bishop DT, Lim HB. School of Sport and Education, Brunel University, Uxbridge, Middlesex, England, UK.  Res Q Exerc Sport. 2011 Sep;82(3):592. http://www.ncbi.nlm.nih.gov/pubmed/21699107

“Slow tempo music was not preferred at any exercise intensity, preference for fast tempo increased, relative to medium and very fast tempo music, as exercise intensity increased.”

This study correlated music with increased grip strength, an excellent indicator of the strength of the neural connection to the muscles through the nervous system…

Effects of pretest stimulative and sedative music on grip strength. Karageorghis CI, Drew KM, Terry PC. School of Physical Education and Sport, Brunel University College, UK. Percept Mot Skills. 1996 Dec;83(3 Pt 2):1347-52. http://www.ncbi.nlm.nih.gov/pubmed/9017751

“Repeated-measures analysis of variance and post hoc tests showed that participants evidenced higher grip strength after listening to stimulative music than after sedative music or a white noise control condition.”

Music can directly effect the autonomic nervous system at high exercise intensities, but what about lower intensity activity? Well, even though it hasn’t been as strongly associated with physiological effects, this study finds that it still might be useful in limiting fatigue…

Effects of music during exercise on RPE, heart rate and the autonomic nervous system. Yamashita S, Iwai K, Akimoto T, Sugawara J, Kono I. Center for Humanity and Sciences, Ibaraki Prefectural University of Health Sciences, Ami, Japan. J Sports Med Phys Fitness. 2006 Sep;46(3):425-30. http://www.ncbi.nlm.nih.gov/pubmed/16998447

“When jogging or walking at comparatively low exercise intensity, listening to a favorite piece of music might decrease the influence of stress caused by fatigue, thus increasing the ”comfort” level of performing the exercise.”

Here’s more research that supports that perceived fatigue levels are lower during submaximal exercise if the trainee is listening to music…

Effects of music tempo upon submaximal cycling performance. Waterhouse J, Hudson P, Edwards B. Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, Liverpool, UK. Scand J Med Sci Sports. 2010 Aug;20(4):662-9. doi: 10.1111/j.1600-0838.2009.00948.x. Epub 2009 Sep 28. http://www.ncbi.nlm.nih.gov/pubmed/19793214

“Healthy individuals performing submaximal exercise not only worked harder with faster music but also chose to do so and enjoyed the music more when it was played at a faster tempo.”

Now that we’ve covered the effects of music during exercise, let’s move on to the recovery period post-exercise.

Effect of different musical tempo on post-exercise recovery in young adults. Savitha D, Mallikarjuna RN, Rao C. Departament of Physiology, Narayana Medical College, Nellore 524 002. Indian J Physiol Pharmacol. 2010 Jan-Mar;54(1):32-6. http://www.ncbi.nlm.nih.gov/pubmed/21046917

“The study concluded that music hastens post exercise recovery and slow music has greater relaxation effect than fast or no music, recovery time being independent of the gender and individual music preference.”

There you have it — music is helpful pre, post, and during exercise to manipulate psychological and physical attributes.

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Sources

Effect of different musical tempo on post-exercise recovery in young adults. Savitha D, Mallikarjuna RN, Rao C. Departament of Physiology, Narayana Medical College, Nellore 524 002. Indian J Physiol Pharmacol. 2010 Jan-Mar;54(1):32-6. http://www.ncbi.nlm.nih.gov/pubmed/21046917

Effects of music tempo upon submaximal cycling performance. Waterhouse J, Hudson P, Edwards B. Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, Liverpool, UK. Scand J Med Sci Sports. 2010 Aug;20(4):662-9. doi: 10.1111/j.1600-0838.2009.00948.x. Epub 2009 Sep 28. http://www.ncbi.nlm.nih.gov/pubmed/19793214

Effects of music during exercise on RPE, heart rate and the autonomic nervous system. Yamashita S, Iwai K, Akimoto T, Sugawara J, Kono I. Center for Humanity and Sciences, Ibaraki Prefectural University of Health Sciences, Ami, Japan. J Sports Med Phys Fitness. 2006 Sep;46(3):425-30. http://www.ncbi.nlm.nih.gov/pubmed/16998447

Effects of pre-exercise listening to slow and fast rhythm music on supramaximal cycle performance and selected metabolic variables. Yamamoto T, Ohkuwa T, Itoh H, Kitoh M, Terasawa J, Tsuda T, Kitagawa S, Sato Y. Research Center of Health, Physical Fitness and Sports, Nagoya University, 464-8601, Japan. Arch Physiol Biochem. 2003 Jul;111(3):211-4. http://www.ncbi.nlm.nih.gov/pubmed/14972741

Effects of pretest stimulative and sedative music on grip strength. Karageorghis CI, Drew KM, Terry PC. School of Physical Education and Sport, Brunel University College, UK. Percept Mot Skills. 1996 Dec;83(3 Pt 2):1347-52. http://www.ncbi.nlm.nih.gov/pubmed/9017751

Musical feedback during exercise machine workout enhances mood. Fritz TH1, Halfpaap J2, Grahl S2, Kirkland A2, Villringer A2. Max Planck Institute for Human Cognitive and Brain Science Leipzig, Germany. Front Psychol. 2013 Dec 10;4:921. doi: 10.3389/fpsyg.2013.00921. eCollection 2013. http://www.ncbi.nlm.nih.gov/pubmed/24368905

Revisiting the relationship between exercise heart rate and music tempo preference. Karageorghis CI, Jones L, Priest DL, Akers RI, Clarke A, Perry JM, Reddick BT, Bishop DT, Lim HB. School of Sport and Education, Brunel University, Uxbridge, Middlesex, England, UK.  Res Q Exerc Sport. 2011 Sep;82(3):592. http://www.ncbi.nlm.nih.gov/pubmed/21699107

The effects of synchronous music on 400-m sprint performance. Simpson SD, Karageorghis CI. School of Sport and Education, Brunel University, West London, Uxbridge, UK. J Sports Sci. 2006 Oct;24(10):1095-102. http://www.ncbi.nlm.nih.gov/pubmed/17115524

The Rotator Cuff is a Delicate Flower

Anyone who has had extensive experience in an activity that requires explosive movement of the upper limb likely realizes the fragility of the rotator cuff. As I always say, playing sports is a great way to get injured. Even non-contact sports like baseball, tennis and swimming carry injury risk, because repetitive overhead arm movement is recognized as one of the primary causes of rotator cuff injuries. However, that isn’t the only cause — those who engage in activities that keep the arm overhead or in a fixed position for extended periods are also at risk — carpenters, hairstylists, painters, etc. Naturally, gym-rats are no strangers to torn rotator cuffs, as bench presses, military presses and heavy overhead lifts can put a tremendous amount of stress on the shoulder (utilizing a neutral grip with the palms facing each other can help to avoid the internal shoulder rotation that a typical pronated grip can cause). Even couch potatoes should be concerned, since poor posture alone can also irritate the architecture of the shoulder over time.

To complicate matters, the rotator cuff can tear instantly from an acute injury, or can be worn down gradually due to impingement. The tear can be partial, in which the attachments to the bone are not completely severed, or a complete tear can occur, where the tendon goes “poof,” to use a totally-scientific term.

So, what should we do about all this? Some preventive measures maybe? Don’t worry, I’ve got you covered…

The muscles of the rotator cuff include:

  • Supraspinatus — abducts the arm at the shoulder joint.
  • Infraspinatus — externally rotates the arm at the shoulder joint.
  • Teres Minor — also externally rotates the arm at the shoulder joint.
  • Subscapularis — depresses the head of the humerus, internally rotates the arm at the shoulder joint.

Together, these muscles function to keep the humeral head in its proper position in the glenohumeral joint. Strengthening them will serve to provide a measure of prevention against rotator cuff injuries. First though, if you think you have an existing tear, or a partial tear, or you have chronic shoulder pain, or your shoulder feels funny, or no matter what manner of shoulder malady you may have — please, see a physician. He/she can diagnose the problem and suggest a course of treatment. A rotator cuff injury may need surgery, or surgery may be avoidable — but only a doctor can tell you.

Now that the disclaimer is out of the way, it’s time for some pre-habilitation.

These exercises will strengthen the rotator cuff and help protect against injury:

  • I-Y-T-W on Stability Ball
  • Band Pull-Aparts
  • Internal Rotation (use band while standing or dumbbell while lying on your side)
  • External Rotation (use band while standing or dumbbell while lying on your side)

Do these 1-2 times per week for 2-3 sets of 10 repetitions each.

A healthy shoulder is a happy shoulder.

Sources

Blevins, FT. “Rotator Cuff Pathology in Athletes.” September 24, 1997.  http://www.ncbi.nlm.nih.gov/pubmed/9327536

Bradley & Jobe. “Rotator Cuff Injuries in Baseball.” December 6, 1988. http://www.ncbi.nlm.nih.gov/pubmed/3231953

Heyward, Vivian. “Advanced Fitness Assessment and Prescription, 6th Edition.” Human Kinetics. 2010.

John, Daniel. “Mass Made Simple.” On Target Publications. Aptos, CA. 2011.

Knopf, Karl G. “Exercise Therapy 3rd Edition.” International Sports Science Association Official Course Text. Carpinteria, CA. 2013.

Nicol, Ashley. “Rotator Cuff Injuries Solved.” Createspace. USA. 2012.

Sitting: Physical Consequences

I’m sure you’re aware of the studies that associate sedentary lifestyles with heart disease, obesity and poor overall health (if you’re not, you will be in a minute). But considering there’s no shortage of cubicle-based jobs that require employees to sit seven or eight hours a day, a sedentary lifestyle is basically forced upon many of us. In efforts to convince people to take responsibility for their actions and choices, it is important not to forget that quite often, people are trapped in unfavorable circumstances. Believe me, when clients tell me they sit at a desk all day, typing on a computer, then go home exhausted, too tired to engage in any sort of exercise… I understand. However, I’m going to be blunt here and assure you that in addition to metabolic disorders, excessive sitting can also cause muscle imbalances in the body that can eventually result in injuries. My sympathy isn’t going to be enough to put you back together when your job or lifestyle causes you to fall apart, but fortunately, I bring more than sympathy to the table.

Here are a few physical consequences of excessive sitting:

  • Tight hip flexors, causing anterior pelvic tilt (a bad case of anterior pelvic tilt will cause the stomach to protrude forward and the butt to tilt backward).
  • Tight hamstrings, which are the culprit in many sports-related injuries.
  • Tight external hip rotators, limiting mobility of the hip joint.
  • Limitation of range of motion in the thoracic and lumbar spine.
  • Assorted aches and pains in muscles and tendons, particularly in the wrists, shoulders, lower legs, back, and neck.
  • Poor posture.

While correction of sitting-related problems can be a complex matter (call my office), preventive measures are an excellent idea for anyone who finds themselves confined to an office chair for multiple hours a day. So how do we go about reducing the risk of these problems?

  • Sit in a manner that is ergonomically efficient: upright posture, relaxed shoulders, and knees equal height or lower than hips.
  • No slouching in your chair or sitting with legs crossed for extended periods of time.
  • Take breaks and stand up as often as possible. Also, frequently check to make sure you’re sitting with proper posture.
  • Do some stretches at the office
    • Wall Lean
    • Thoracic Extension
    • Hip Flexor Lunge with Overhead Reach
  • And some strengthening exercises at home
    • I-Y-T-W on Stability Ball
    • Plank with Alternating Leg Lifts
  • Myofacial Release with foam roller or tennis ball

Oh, by the way, remember those studies I mentioned earlier? The ones that indicate that too much sitting can pose health hazards? Well, here are links to one or two of them, click away:

Sitting time and mortality from all causes, cardiovascular disease, and cancer.

Too much sitting: the population health science of sedentary behavior.

Sitting time and all-cause mortality risk in 222 497 Australian adults.

Sitting and cardiovascular morbidity and mortality.

Occupational sitting time and overweight and obesity in Australian workers.

Breaking up prolonged sitting reduces postprandial glucose and insulin responses.

Leisure time spent sitting in relation to total mortality in a prospective cohort of US adults.

Role of low energy expenditure and sitting in obesity, metabolic syndrome, type 2 diabetes, and cardiovascular disease.

Impact on hemostatic parameters of interrupting sitting with intermittent activity.

Too much sitting–a health hazard.

I’m sure you get the point by now. Besides, copying all these links is giving me carpal tunnel syndrome.

I’ll be doing a workshop in the Philadelphia burbs on this very topic (what an amazing coincidence!) in late January, so if you want to learn how to fix yourself up, then come and visit me.

Sources

Knopf, Karl. “Exercise Therapy, Third Edition.” Carpinteria, CA. International Sports Sciences Association. 2013

Schoberth, Hans. “Sitting, Sitting Injuries, and Seats.” Berlin and Heidelberg: Springer-Verlag.

Wonders of Water

Water is the largest component of the human body and the primary component of all body fluids.

The main sources of water for the human body are:

  • Pre-formed Water: Ingested liquids from food and drink that have been absorbed through the gastrointestinal tract.
  • Metabolic Water: Produced via dehydration synthesis reactions of anabolism.

When more water is lost than gained by the body, the resulting dehydration stimulates thirst by decreasing saliva production, increasing osmotic pressure, and decreasing blood volume which causes the kidneys to release renin, stimulating the sensation of thirst in the hypothalamus. When the sensation of thirst increases, a person’s resulting consumption of water restores normal fluid volume. Water movement in and out of body compartments is primarily due to osmosis. Electrolytes help control the process of osmosis and maintain acid-base balance for normal cellular activity. Electrolytes also carry electrical currents, which controls secretion of certain hormones and neurotransmitters.

Sweating results in loss of fluids that impact physiological function. Obviously, that’s why replacing fluids during strenuous exercise is important. Dehydration can have a very negative impact on physical performance and adequate fluid intake during exercise assists in replacement of intracellular water. The benefits of proper hydration during exercise can include increased blood volume, lower core temperature, and reduced muscle glycogen use. These and other factors combine to maintain performance levels over the duration of prolonged physical exertion.

Here’s a study that evaluated effectiveness of hydration on work capacity and physical stress on groups given plain water, sports drinks, or no liquid at all:

ACUTE PHYSIOLOGICAL RESPONSE TO INDOOR CYCLING WITH AND WITHOUT HYDRATION; CASE AND SELF-CONTROL STUDY. Ramos-Jiménez A, Hernández-Torres RP, Wall-Medrano A, Torres-Durán PV, Juárez-Oropeza MA, Solis Ceballos JA. Nutr Hosp. 2013 Septiembre-Octubre;28(5):1487-1493. Department of Basic Sciences. Biomedical Sciences Institute. Autonomous University of Ciudad Juárez. México. http://www.ncbi.nlm.nih.gov/pubmed/24160205

“Oral rehydration drinks help maintain physical capacity and hydration during exercise… Liquid intake with or without electrolytes does not affect work capacity, and they are equally effective as hydration sources during 90 min of InC at strong and very strong intensities. Body temperature is the most sensitive variable detected by the subject’s hydration status during exercise.”

Water proved equally effective as sports drinks for hydration, maintaining body temperature and work capacity. Exciting to me because water is less expensive than sports drinks (just kidding, sort of). But this isn’t to minimize the role of sports drinks, as sodium replacement is occasionally necessary as well for proper electrolyte balance, particularly during physical exertion in hot temperatures. Sodium is crucial for not only conduction of impulses in muscle and nervous tissue, but it also assists in maintenance of fluid and electrolyte balance by creating extra-cellular fluid and osmotic pressure.

The human body functions better when it’s properly hydrated. This is especially true of muscle cells. I suggest you do what I do and carry a bottle of water with you wherever you go. Sip it at the first signs of thirst. There’s never, ever any advantage to letting yourself become dehydrated, however there are myriad negatives to that equation. May I also suggest that you invest in a quality water filter and a BPA-free bottle to minimize potential toxins. In an increasingly polluted world, it’s worth the effort to make sure your water sources are as clean as possible. Because if you’re smart — and, ahem, I’m sure that anyone reading this blog certainly must be pretty damn smart — you’ll be drinking a lot of it.

Sources

ACUTE PHYSIOLOGICAL RESPONSE TO INDOOR CYCLING WITH AND WITHOUT HYDRATION; CASE AND SELF-CONTROL STUDY. Ramos-Jiménez A, Hernández-Torres RP, Wall-Medrano A, Torres-Durán PV, Juárez-Oropeza MA, Solis Ceballos JA. Nutr Hosp. 2013 Septiembre-Octubre;28(5):1487-1493. Department of Basic Sciences. Biomedical Sciences Institute. Autonomous University of Ciudad Juárez. México. http://www.ncbi.nlm.nih.gov/pubmed/24160205

Fox, Stuart. “Human Physiology.” Mcgraw Hill. 2008.

Sherwood, Lauralee. “Human Physiology: From Cells to Systems, Edition 7.” Cengage. 2008.

Widmaier, Eric P. “Vander’s Human Physiology: The Mechanisms of Body Function, 12th Edition.” Mcgraw Hill. 2010.

Thyroid Hormones

Thyroid hormones don’t get as much attention in fitness world as their more anabolic relatives, but proper thyroid function is essential for regulation of metabolic rate and body temperature, in addition to other crucial biological responsibilities. This makes the thyroid a topic worthy of further study for exercise enthusiasts — don’t underestimate the effect of thyroid function on physical performance and body composition. Thyroid hormones are responsible for the regulation of oxygen use, basal metabolic rate, and cellular metabolism and developmentBy stimulating cellular oxygen use for the production of ATP, thyroid hormones increase basal metabolic rate, which is the rate of oxygen consumption at rest. Cells use more oxygen to produce ATP — this causes body temperature to rise as more heat is given off. This maintenance process of body temperature (thermoregulation) is called the calorigenic effect.

As to the regulation of metabolism, thyroid hormones prompt protein synthesis and increase the use of glucose for production of ATP. They work together with growth hormone and insulin to accelerate tissue growth.  Secretion from the thyroid is controlled by both iodine levels and negative feedback systems involving the hypothalamus and pituitary. The negative feedback systems are triggered by factors such as environmental cold, high altitude, and hypoglycemia. The thyroid gland is the only endocrine gland that stores its product in very large quantities. Thyroid follicles fill the thyroid gland, where they manufacture Thyroxine (T4) and Triiodothyronine (T3). Normally, T4 is produced on greater amounts, but isn’t as potent as T3. These are both lipid soluble and enter the blood by diffusing into the plasma membrane. In the blood, they combine with transport proteins, particularly thyroxine-binding globulin. The majority of T4 converts into T3 when in the bloodstream, which is the more active of the two forms. For this reason, T4 functions bascially as a prohormone. Inadequate conversion of T4 to T3 can result in hypothyroidism.

I know, it’s all very science-y. Well, strap in, because we’re about to get more academic.

Here’s a study that investigates thyroid function in pro cyclists:

Thyroid hormones may influence the slow component of VO(2) in professional cyclists. Lucía A, Hoyos J, Pérez M, Chicharro JL.Departamento de Ciencias Morfológicas y Fisiología, Universidad Europea de Madrid, Spain.  http://www.ncbi.nlm.nih.gov/pubmed/11405918

“We analyzed the relationship between the plasma concentrations of several hormones (testosterone [T], follicle-stimulating [FSH] and luteinizing hormone [LH], cortisol [C], 3,5,3′-triiodothyronine [T(3)], thyroxine [T(4)], and thyrotrophin [TSH]) and the magnitude of the VO(2) slow component (Delta VO(2)) in a group of nine professional road cyclists (26+/-2 years). Plasma concentrations of T(3) and T(4) were inversely correlated (p<0.05) with Delta VO(2) (r=-0.72 and rr=-0.66, respectively), suggesting, at least partly, and association between thyroid basal function and the VO(2) slow component of euthyroid elite endurance athletes during constant-load intense exercise.”

T3 and T4 ended up being inversely correlated, which meant that they didn’t rise or fall together. Remember, T4 is basically the prohormone that converts to the T3 hormone.

The following study gives a look into cardiovascular function in patients with thyroid disease:

Differences in heart rate profile during exercise among subjects with subclinical thyroid disease. Maor E, Kivity S, Kopel E, Segev S, Sidi Y, Goldenberg I, Olchovsky D.Leviev Heart Institute, Chaim Sheba Medical Center. Oct;23(10):1226-32. doi: 10.1089/thy.2013.0043. http://www.ncbi.nlm.nih.gov/pubmed/23777550

“Clinical thyroid disease is associated with changes in the cardiovascular system, including changes in heart rate during exercise… Subjects with SCHypoT showed a trend toward a lower resting heart rate (75±13 vs. 77±15 bpm, p=0.09) and had a significantly lower recovery heart rate (88±12 vs. 90±13 bpm, p=0.035). Conclusions: Subjects with SCTD have a significantly different heart rate profile during rest, exercise, and recovery.”

The above makes clear the importance of the thyroid in relation to exercise, but can exercise affect thyroid hormone production in a similar way as it can GH and Testosterone? Well, let’s find out:

Exercise intensity and its effects on thyroid hormones. Figen Ciloglu, Ismail Peker1, Aysel Pehlivan, Kursat Karacabey, Nevin İlhan, Ozcan Saygin & Recep Ozmerdivenli. University of Gaziantep, The School of Physical Education and Sports, Gaziantep, Turkey. http://www.nel.edu/26-2005_6_pdf/NEL260605A14_Ciloglu.pdf

The results of this study show that exercise performed at the anaerobic threshold (70% of maximum heart rate, lactate level 4.59 ± 1.75 mmol/l) caused the most prominent changes in the amount of any hormone values. While the rate of T4, fT4, and TSH continued to rise at 90% of maximum heart rate, the rate of T3 and fT3 started to fall. Conclusions: Maximal aerobic exercise greatly affects the level of circulating thyroid hormones.”

To summarize, as intensity escalates, more T4 is produced, but less is converted to T3. Keep in mind that the change in homeostasis is temporary, because much like the case with GH and Testosterone levels, the circulating hormones will slowly return to pre-exertion levels after the activity stops.

Moving on, we’ll look at one more study, this one comparing thyroid hormonal response to differing exercise protocols — Interval training versus steady state cardio in highly trained test subjects.

Thyroid hormonal responses to intensive interval versus steady-state endurance exercise sessions. Hackney AC, Kallman A, Hosick KP, Rubin DA, Battaglini CL.Endocrine Section-Applied Physiology Laboratory, Department of Exercise & Sport Science, University of North Carolina, Chapel Hill, North Carolina. http://www.ncbi.nlm.nih.gov/pubmed/22450344

IE results in a suppressed peripheral conversion of T₄ to T₃ implying that a longer recovery period is necessary for hormonal levels to return to normal following IE compared to SEE. These findings are useful in the implementation of training regimens relative to recovery needs and prevention of over-reaching-overtraining.”

The verdict is that the intense interval training resulted in a longer time period before T4 to T3 conversion restarted at normal pre-exercise levels. Useful information for programming a fitness routine for someone suffering from hypothyroidism.

A healthy metabolism depends on a properly functioning thyroid. Obviously, that means body composition and fat loss are closely tied to it also. For those with hypothyroidism, exercise in combination with medical treatment can be extremely helpful in maintaining a healthy body composition and improving thyroid function over the long term.

Sources

ACSM’s American College of Sports Medicine. The recommended quantity and quality of exercise for developing and maintaining
cardiorespiratory and muscular fitness in healthy adults. Med Sci Sports Exerc 1990; 22: 265–274.

Differences in heart rate profile during exercise among subjects with subclinical thyroid disease. Maor E, Kivity S, Kopel E, Segev S, Sidi Y, Goldenberg I, Olchovsky D.Leviev Heart Institute, Chaim Sheba Medical Center. Oct;23(10):1226-32. doi: 10.1089/thy.2013.0043. http://www.ncbi.nlm.nih.gov/pubmed/23777550

Exercise intensity and its effects on thyroid hormones. Figen Ciloglu, Ismail Peker1, Aysel Pehlivan, Kursat Karacabey, Nevin İlhan, Ozcan Saygin & Recep Ozmerdivenli. University of Gaziantep, The School of Physical Education and Sports, Gaziantep, Turkey.  http://www.nel.edu/26-2005_6_pdf/NEL260605A14_Ciloglu.pdf

Hackney AC, McMurray RG, Judelson DA, Harrell JS.. Relationship between caloric intake, body composition, and physical activity
to leptin, thyroid hormones, and cortisol in adolescents. Jpn. J Physiol. 2003; 53:475–9.

Huang WS, Yu MD, Lee MS, Cheng CY, Yang SP, Chin HM, Wu SY. Effect of treadmill exercise on circulating thyroid hormone measurements. Med Princ Pract. 2004;13:15–9.

Lucia A, Hoyos J, Perez M, Chicharro JL.Thyroid Hormones may influence the slow component of VO2 in professional cyclists. Japanese Journal of Physiology 2001; 51:239–242.

Thyroid hormonal responses to intensive interval versus steady-state endurance exercise sessions. Hackney AC, Kallman A, Hosick KP, Rubin DA, Battaglini CL.Endocrine Section-Applied Physiology Laboratory, Department of Exercise & Sport Science, University of North Carolina, Chapel Hill, North Carolina. http://www.ncbi.nlm.nih.gov/pubmed/22450344

The Athlete’s Heart

No, the heart I’ll be discussing in this blog entry isn’t metaphorical triumph of the human spirit in regards to sports — it’s about the actual adaptation the circulatory system of an athlete makes in response to the stimulus of endurance training. Yeah, the real athlete’s heart. I know, gross, right?

The most notable adaptations the body makes to cardiovascular exercise stimulus include:

  • Reduced heart rate during submaximal exercise and potential reduced heart rate during maximal exercise
  • Increase in stroke volume during exercise
  • Increase in the mass and chamber size of the left ventricle
  • Increase in capillary density and recruitment, which facilitates oxygen delivery to the contracting muscles

The cardiovascular system is made up of blood, blood vessels, and, of course, the heart.

During exercise, the primary functions of the cardiovascular system are to deliver oxygen to skeletal muscles and remove carbon dioxide and heat from contracting muscles. The cardiovascular system also is responsible for the maintenance of mean arterial blood pressure as exercise intensity increases.

Cardiac output refers to the volume of blood pumped by the left ventricle of the heart. It is a combination of the heart rate (beats per minute) and stroke volume (amount of blood pumped with each beat). Endurance training increases maximal cardiac output, which increases the maximal level of oxygen delivery to the body’s tissues. The heart of an endurance athlete generally has a cardiac output much higher than that of an untrained person. Long-term adherence to a proper cardiovascular exercise program will create adaptations in the heart to increase stroke volume, which is the amount of blood pumped from a ventricle with each heartbeat. It is this increase in stroke volume that determines the level of cardiac output.

Physical exertion increases the demand for oxygen in the muscles. VO2 Max is widely viewed as a measure of assessment regarding a person’s aerobic athletic potential. VO2 Max is the capacity of the body to incrementally supply itself with oxygen during physical effort. Along with respiration, the oxidative potential of the muscles, and central nervous system motor drive, circulation is a physiological determinant of VO2. The body’s ability to distribute oxygenated blood in the contracting muscles is obviously a crucial component of physical endurance.

Blood volume refers to red blood cells and blood plasma in the circulatory system. Increasing blood volume increases the efficiency of the heart by assisting it to pump more blood per beat. Additional red blood cells transport more oxygen to muscles, allowing them to perform at higher intensities for longer periods of time. Erythropoietin — better known as EPO — is a hormone that signals cells to produce more red blood cells. When synthetic EPO is added to the body, uh… hypothetically, in the form of injection into a professional cyclist, the expansion of plasma volume and production of additional red blood cells can effectively increase VO2 max, which, of course, provides the athlete with higher levels of endurance. If you’re not as fond of injecting synthetic substances into yourself as cyclists are, similar adaptation can be achieved by prolonged training at high altitudes. This is the reason why high altitude locations like Big Bear Lake, California (surface elevation 6,750), have been popular training camp locations for boxers — a sport that requires superlative cardiovascular conditioning… oh, and for those of you that were expecting metaphor after reading the title — boxing also requires a “big heart”. There. Happy now?

There you have it — the abridged version of the literal athlete’s heart. Metaphor was never my strong suit. Who do I look like to you, Mark Twain?

Sources

Ekblom B and Hermansen L. Cardiac output in athletes. J Appl Physiol 25: 619–625, 1968.

Grimby G, Nilsson NJ, and Saltin B. Cardiac output during submaximal and maximal exercise in active middle-aged athletes. J Appl Physiol 21: 1150–1156, 1966.

National Center for Biotechnology Information. EPO erythropoietin. http://www.ncbi.nlm.nih.gov/gene/2056

Hormones and Resistance Training

The endocrine system is made up of endocrine glands, which include the pituitary, thyroid, parathyroids, adrenals, and pineal glands. Additionally, other organs of the body contain endocrine tissue, these being the hypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, and heart. The products of endocrine glands secrete into the space around secretory cells, then are diffused into capillaries and carried in the bloodstream.

The endocrine system, along with the nervous system, coordinate the functions of body systems. The nervous system prompts contraction of muscles, which causes secretion from glands. When the endocrine system releases hormones into the bloodstream, they are then carried to cells where they elicit responses. These responses may occur within seconds, or they may take hours to peak.

With regards to resistance training, the style of training being performed can help dictate the effects of the body’s systems. For example, heavy, low rep weightlifting with long rest periods works mainly by increasing the density of myofibrils within muscle cells and conditioning the nervous system to make impulses sent through neural pathways to muscles more efficient. More practice with movements results in more muscular force generation with that particular movement pattern. An example of this style of training would be barbell snatches for 3 sets of 3 repetitions with 5 minute rest periods between sets. By contrast, lighter loading parameters, more sets, and higher repetitions lean more towards sarcoplasmic hypertrophy, filling muscle cells with fluid — typical bodybuilding style workouts are geared more towards this purpose. As I’ll discuss in a minute though, higher volume routines can elicit heightened hormonal responses. Obviously, there is neuroendocrine overlap regardless of training style, but my point is that the volume and intensity of effort can be manipulated to achieve varying physique and performance goals.

I’ll cover myofibrillar and sarcoplasmic hypertrophy in more detail in a future article, but for the moment do me a favor and visualize an overly vague (and potentially unfair) generalization: Primarily myofibrillar hypertrophy = olympic weightlifter. Primarily sarcoplasmic hypertrophy = “pumped up” Jersey Shore nightclub attendee.

Ah, I digress. Back to hormones… for now, let’s focus on the most buzz-worthy glandular secretions in the gym:

Testosterone is a steroid hormone, having both androgenic and anabolic effects. It is produced primarily by the testes in males, and to a lesser extent, the adrenal glands. The metabolic effects of testosterone include muscle mass, strength, and energy. The anabolic effects of testosterone include muscle tissue growth and bone density.

Growth Hormone is a protein based peptide hormone. It is secreted by the pituitary gland for the purpose of cell regeneration. The primary action of GH is the growth of body cells. It also has multiple metabolic effects, most notably the stimulation of protein synthesis, inhibition of protein breakdown, and elevating blood glucose concentration.

The difference between a peptide hormone and a steroid hormone is a steroid hormone binds directly to cells, where peptide hormones use secondary messengers. GH, being a peptide, uses assistance from Insulin-like Growth Factor-1 for cellular response. IGF-1 is produced mostly by the liver, with GH being the primary stimulator.

GH causes cellular growth by increasing the speed of amino acids as they enter into cells. This increases protein synthesis. GH also decreases the breakdown of proteins used to generate ATP, instead using fat oxidation for energy. This means that increased levels of GH in the body cause fat to burn as fuel instead of muscle. Additionally, GH affects carbohydrate metabolism, causing the liver to convert glycogen into glucose.

If you’re wondering why our beloved professional athletes are so infatuated with synthetic Testosterone, GH and IGF-1 supplementation, wonder no more. Simply put: optimized hormonal release = enhanced muscle hypertrophy, less stored fat, and more efficient metabolic processes.

Resistance exercise has long been known to elicit a hormonal response to stimulus. As long as the volume (sets and repetitions) and intensity (percentage of 1-rep maximum) of resistance exercise is sufficient, Testosterone and Growth Hormone are elevated following a lifting session. Levels generally peak about 15-30 minutes after lifting.

A study conducted by Kraemer and Ratamess at The University of Connecticut states:

“Protocols high in volume, moderate to high in intensity, using short rest intervals and stressing a large muscle mass, tend to produce the greatest acute hormonal elevations (e.g. testosterone, GH and the catabolic hormone cortisol) compared with low-volume, high-intensity protocols using long rest intervals.”

The full abstract can be found here: http://www.ncbi.nlm.nih.gov/pubmed/15831061

The above findings suggest that a greater volume of training has a larger effect on hormonal release, provided that the training isn’t so debilitating that excess amounts of cortisol begin to circulate.

The highly successful Bulgarian olympic weightlifting teams of the 1970’s coached by Ivan Abadjiev kept heavy training sessions limited to 45 minutes each because they believed that testosterone production leveled off after that point. While there isn’t much scientific evidence to support the 45 minute theory, it’s hard to argue with the Bulgarian methods. Bulgarians have won 36 olympic weightlifting medals even though their country has a population of approximately 7,364,570. To put that accomplishment into perspective, the United States has won 43 olympic weightlifting medals, with an approximate population of 316,123,000. Yes, the Bulgarian teams have, in the past, occasionally been caught doping, but so has every other nation that has succeeded in international athletic competition. Their steroids aren’t better than everyone else’s steroids.

Some bullet points to, uh… synthesize this information…

To maximize testosterone and GH levels with resistance exercise:

  • Use lifts that recruit a large amount of muscle mass (Example: Squat, Bench Press, Row).
  • Perform a sufficient volume (sets x reps x load) of resistance training (Example: 3-6 sets x 6-8 repetitions per lift).
  • Utilize compressed rest periods between sets, ideally between 30-90 seconds.
  • Keep total training session times long enough to maximize Testosterone and GH levels, but minimize Cortisol. Though there is a dearth of scientific study on the topic, the anecdotal evidence supporting 45-60 minutes of intense exercise is strong.
  • In addition to exercise and nutritional choices, lifestyle factors play a huge part in maintaining hormonal balance. The most notable of these elements are getting adequate sleep and lowering stress levels.

Though these general tips can prove useful, keep in mind that each human body in unique. Use scientific processes to experiment for your own purposes: hypothesis, controlled variables, observation, testing, analysis, and modification. Accordingly, if you’re not already keeping a detailed training journal to track your progress, start one immediately.

More detail on these topics will be included future articles…

Sources

Faigin, Rob. “Hormonally Intelligent Exercise.” Extique. 2004.

Karp, Hannah. “Heavy Lifting, No Rest, Candy: the Bulgarian Method.” The Wall Street Journal. June 21, 2011. http://online.wsj.com/article/SB10001424052702304070104576397543601842556.html

Kraemer WJ. “Endocrine responses to resistance exercise.” Med Sci Sports Exerc. 1988 Oct;20(5 Suppl):S152-7. Exercise Physiology Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760-5007.

Kraemer WJ, Ratamess NA. “Hormonal Responses and Adaptations to Resistance Exercise and Training.” Sports Med. 2005;35(4):339-61. Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, 06269, USA.

Poliquin, Charles. “Five Lessons I Learned from Ivan Abadjiev.” November 11, 2010.  http://www.charlespoliquin.com/ArticlesMultimedia/Articles/Article/491/Five_Lessons_I_Learned_from_Ivan_Abadjiev.aspx

The Medical Biochemistry Page. http://themedicalbiochemistrypage.org/growth-factors.php#igf1

Tsatsouline, Pavel. “Power To The People.” Dragon Door Publications. 1999.

Verkhoshansky, Yuri. “Supertraining, 6th edition.” 2009.

Wikipedia. “Bulgaria.” http://en.wikipedia.org/wiki/Bulgaria

Wikipedia. “United States.” http://en.wikipedia.org/wiki/United_States

Zatsiorsky, Vladimir. “Intensity of Strength Training Fact and Theory: Russian and Eastern European Approach.” Biomechanics Lab The Pennsylvania State University, University Park, Pennsylvania and Central Institute of Physical Culture – Moscow, Russia