Exercise, hormones and weight loss

Regular exercise provides many physical, mental, and physiological benefits. One category of benefits is the positive impact that exercise has on many of your body's hormones, resulting in more efficient metabolism, better health, and weight loss.

Hormones are chemical messengers within your body that affect almost all aspects of human function. Following is a list of your eight hormones, their function, and how regular exercise affects each hormone.

1. Growth Hormone

Growth hormone stimulates protein synthesis (muscle tone/development), and affects the strength of your bones, tendons, ligaments, and cartilage. During exercise, it decreases use of glucose and increases use of fat as a fuel during exercise. This helps to reduce body fat and to keep blood glucose at a normal level which helps you to exercise for a longer period of time. Release of growth hormone from the pituitary gland in the brain is increased with increasing aerobic exercise time, especially more intense exercise such as interval training.

2. Endorphins

An endogenous opioid from the pituitary gland, endorphins block pain, decrease appetite, create a feeling of euphoria (the exercise high), and reduce tension and anxiety. Blood levels of endorphins increase up to five times resting levels during longer duration (greater than 30 minutes) aerobic exercise at moderate to intense levels, and also during interval training. Also, after several months of regular exercise, you develop an increased sensitivity to endorphins (a higher high from the same level of endorphins), and endorphins that are produced tend to stay in your blood for a longer period of time. This makes longer duration exercise easier (you're feeling no pain) and it causes your exercise high to last for a longer period of time after exercise.

3. Testosterone

An important hormone in both males and females, testosterone maintains muscle tone/volume/strength, increases basal metabolic rate (metabolism), decreases body fat, and produces feelings of confidence. It is produced by the ovaries in females and by the testes in males. Females have only about one tenth the amount of testosterone produced by males. Production of testosterone in females begins to decline as a woman begins to approach menopause and in males it begins to decline in his forties.

For men and women, blood levels of testosterone increase with exercise, beginning about 20 minutes into an exercise session. Blood levels may remain elevated for one to three hours after exercise. Testosterone increases the libido both in men and women. Heart has highest testosterone receptors, thus testosterone enhances the functions of the heart and protects it.

4. Estrogen

The most biologically active estrogen, 17 beta estradiol, increases fat breakdown from body fat stores so that it can be used and fuel, increases basal metabolic rate (metabolism), elevates your mood and makes your skin smooth and supple. This hormone is at much higher blood levels in females, but the ovaries begin to produce less of it as a woman begins to approach menopause. The amount of 17 beta estradiol secreted by the ovaries increases with exercise, and blood levels may remain elevated for one to four hours after exercise.

5. Thyroxin (T4)

A hormone produced by the thyroid gland, thyroxine raises the metabolic rate ("metabolism") of almost all cells in the body. This increase in "metabolism" helps you to feel more energetic and also causes you to expend more calories; it is thus is important in weight loss. Blood levels of thyroxine increase by about 30% during exercise and remain elevated for several hours afterward - this period of time is increased by an increase in intensity and/or duration of exercise. Regular exercise also increase thyroxine levels at rest.

6. Epinephrine

A hormone produced primarily by the adrenal medulla, epinephrine increases the amount of blood the heart pumps and directs blood flow to where it's needed. It stimulates breakdown of glycogen (stored carbohydrate) in the active muscles and liver to use as fuel. It also stimulates the breakdown of fat (in stored fat and in active muscles) to use as fuel. The amount of epinephrine released from the adrenal medulla is proportional to the intensity and duration of exercise.

7. Insulin

Insulin is an important hormone in regulating (decreasing) blood levels of glucose ("blood sugar") and in directing glucose, fatty acids, and amino acids into the cells. Insulin secretion by the pancreas is increased in response to a rise in blood sugar as is often the case after a meal. Typically, the larger the meal, or the greater the quantity of simple sugars consumed, the larger the insulin response. This is why it is best to eat small frequent meals and to limit consumption of sugar and of processed bread, pasta and rice. The whole grain (non- processed) versions of those products are much healthier choices.

Blood levels of insulin begin to decrease about 10 minutes into an aerobic exercise session and continue to decrease through about 70 minutes of exercise. Regular exercise also increases a cell's sensitivity to insulin at rest, so that less is needed.

8. Glucagon

A hormone that is also secreted by the pancreas, the job of glucagon is to raise blood levels of glucose ("blood sugar"). When blood sugar levels get too low, glucagon is secreted and causes stored carbohydrate (glycogen) in the liver to be released into the blood stream to raise blood sugar to a normal level. It also causes the breakdown of fat so that it can be used as fuel. Glucagon typically begins to be secreted beyond 30 minutes of exercise when blood glucose levels may begin to decrease. As you can see, exercise has a powerful impact on your hormones, ultimately resulting in weight loss, a sense of well-being, and better general health. So next time you're exercising, think about all the wonderful things that are happening to your hormones. It might even make you want to do more exercise!

 Thus, it is evident that exercise has an important role in the release and withdrawal of hormones, by enlarge optimizing it for body functions and weight loss, which is a precursor of good health and graceful aging.

Regulation of type 2 diabetes using exercise

A regular exercise regimen in diabetes – afflicted helps in better control of blood sugar and reduces the demand for medication by 20%. Patients with Type 2 diabetes, who regularly exercise, find that their blood glucose is better controlled, but on a day they miss their physical activity program, the glucose level tends to rise. Thus exercise is now considered an important tool for the long management of diabetes.

Precautions to be taken by patients before an exercise program

1. check your random blood sugar level before and after exercise

2. blood glucose should be above 100 mg/dl and  less than 250 mg/dl.

3. no symptoms of retinopathy, (damage to the blood vessels of the eye), neuropathy (damage to the nerves and circulation to extremities), or nephropathy (kidney damage)

4. no cardiovascular problems such as angina, embolism, or aneurysm

5. wear a well cushioned pair of walking shoes with antiperspirant socks

Exercise recommendation

American diabetes association recommends the following protocol of exercise to be followed for patients with type 2 diabetes:

1. Regular aerobic exercises like walking, jogging, swimming for 30 min 6 days a week @ moderate intensity.

2.  Regular resistance training for patients without the above said complications 3 days a week , working 8-12 repetitions per set, targeting  all major muscle groups.

Effects of exercise on type 2 diabetes

1. Lowers the blood glucose levels

2. Opens the muscle receptors for peripheral glucose absorption

3. Increases insulin sensitivity

4. Greater mobilization of fat, enabling weight loss.

Exercise response to pain

What is pain?

“An unpleasant sensory or emotional experience associated with actual or potential tissue damage. Pain is an unpleasant feeling that is conveyed to the brain by sensory neurons. The discomfort signals actual or potential injury to the body. However, pain is more than a sensation, or the physical awareness of pain; it also includes perception, the subjective interpretation of the discomfort. Perception gives information on the pain's location, intensity, and something about its nature. The various conscious and unconscious responses to both sensation and perception, including the emotional response, add further definition to the overall concept of pain.”

A literature review on “impact of exercise on pain”

There is enough evidence that there is a considerable reduction in pain after resistance training based on the research done by KF Koltyn and RW Arbogast. The main objective was to assess the influence of resistance exercise on pain threshold and pain ratings. After an extensive research done on various subjects there was a conclusion that pain ratings were definitely lower after a session of resistance training and that the pain threshold was increased subsequent to the session. Resistance exercise consisted of 45 minutes of lifting three sets of 10 repetitions at 75% of an individual's one repetition maximum.

“Exercise improves your pain threshold,” says Trent Nessler, PT, DPT, MPT, a vice president with Champion Sports Medicine in Birmingham, Ala. “With chronic pain, your pain threshold drops -- in other words, it takes less pain to make you feel more uncomfortable. With cardiovascular, strengthening, and flexibility exercise, you can improve that pain threshold.”

Studies also show a gross improvement in Fibromyalgic impact questionnaire (FIQ) with reference to pool exercises. For those with chronic pain, exercise may be the last thing you feel like doing. However, a new study finds that getting active may actually help alleviate some pain, including that related to nerve damage. Neuropathic pain or pain caused by nerve damage is a complex problem in which the nerve fibers may be damaged, dysfunctional or injured causing symptoms such as shooting and burning pain and tingling and numbness. The impact of nerve fiber injury includes a change in nerve function both at the site of the injury and the areas that surround it. Some common causes of neuropathic pain include diabetes, multiple sclerosis, shingles, chemotherapy treatment and alcoholism

How exercise relieves pain?

Improves flexibility. Although it may be more comfortable now to avoid moving painful joints, in the long run, this can cause joints to stiffen. In the worst case, you could lose the use of the painful joint. Moving your joints helps relieve stiffness and keeps them flexible. It increases your circulation within the joints and dissipates the noxious metabolites that irritate the nerve endings causing pain.
Strong muscles. Exercise strengthens muscles, and strong muscles mean better support and protection for painful joints. Inactivity, on the other hand, can cause muscles to become weaker and less able to support painful joints. Exercise improves circulation, provides nutrition to the muscle tissues and removes the wastes that induce pain
Denser bones. Arthritis-related inflammation, as well as the corticosteroids often used to treat it, can lead to loss of bone density, causing bones to become brittle and prone to fracture. Your bones, like your muscles, respond to exercise by growing stronger, so more exercise could mean fewer fractures. 
A healthy heart. A regular exercise program is one of the best lines of defense against heart disease. Thus reduces general debility by conditioning your heart and lungs to make you more mobile and gain efficiency through cardiovascular endurance. A regular exercise program may improve or help you maintain your ability to perform your daily activities
Increased sense of well-being. Living with pain can lead to a cycle of painful emotions and depression. Exercise can help break the cycle by reducing pain, boosting your mood, and improving your sense of well-being by the release of endorphins and serotonins. Exercise also reduces the bouts of depression and anxiety caused by inability, by enlarge also increases the pain threshold of a person.
More benefits. If that's not enough, consider these other benefits of a regular exercise program: increased energy, better sleep, weight control, and the opportunity to socialize with friends.

Thus a supervised and well-designed exercise protocol done with a rehabilitative pain management motive can relieve pain and give the best possible results.

Exercise response to medication

The use of medications, whether prescription or over the counter, is common in people with active lifestyles. The health and fitness professional should be aware of how certain medications may affect his or her client’s ability to exercise. As our population is aging, it also is important to understand how commonly prescribed medications may affect the older adult who chooses to exercise.

ANALGESICS: NSAIDS, ACETAMINOPHEN, AND OPIOIDS

NSAIDs are one of the most commonly used classes of medications. Names of generic medications in this class include naproxen and ibuprofen. They do have a pain-relieving effect, but their anti-inflammatory effect is overrated. There have been no studies to date showing that NSAIDS have any adverse effect on one’s ability to exercise.

It is important to note that there are theoretical risks of delayed healing in soft-tissue injuries such as sprains and strains in people taking NSAIDs . There also is a risk of acute kidney injury with their use in individuals who are dehydrated. As a result, endurance athletes should not take these medications before their event. Gastrointestinal bleeding is a major concern, especially with older clients; between 7,500 and 16,500 deaths from gastrointestinal bleeding in the U.S. annually are attributed to NSAID use . This class of medication is being investigated by the U.S. Food and Drug Administration for increasing the risk of heart attacks and should be used with caution in those with existing heart disease. Finally, its use may exacerbate asthma in some athletes with this condition.

Another commonly used over-the-counter pain reliever is acetaminophen. There have been no studies showing adverse effects on exercise with its use. Its main risk is liver toxicity for those who take more than 4 g per day, which is above the recommended maximum dose.

The last class of analgesics is opioids, commonly referred to as narcotics. Medications in this class include codeine, hydrocodone, oxycodone, and morphine. They have been proven to decrease exercise performance by delaying reaction time and causing sedation. They commonly cause constipation and have a high addiction potential. They also are banned by the World Anti-Doping Agency (WADA).

Oral contraceptives commonly are used by active females to treat amenorrhea and painful menses and for contraception. Concerns over their use with female athletes include fluid retention, weight gain, nausea, headache, and a small risk in developing deep vein thrombosis in those with a genetic predisposition to this condition. Two small studies have shown a slight decrease in V˙O_2max (aerobic capacity) with their use. Larger studies are needed to confirm these results .

ANTIBIOTICS

There is concern that antibiotics may be overused in athletic populations. The main class of antibiotics that may affect active people is the flouroquinolones. Generic names for these medications include ciprofloxacin, moxifloxacin, and levofloxacin. There is a slight increased risk of tendon injuries in those taking this class of medication. About one half of these tendon injuries have occurred within the first 6 days of treatment . This is a rare event occurring in 1 to 3 cases per 1,000 patients; however, it may make sense to cut back on the intensity of resistance training while clients are on this class of antibiotics.

STIMULANTS/SYMPATHOMIMETICS

Stimulants commonly are used by student athletes to treat attention-deficit disorder. Common names of generic medications in this class include amphetamine, dextroamphetamine, and methylphenidate. Stimulants have been controversial in terms of their ability to enhance performance. Some studies have shown enhanced concentration, increased alertness, decreased pain, decreased fatigue, and increased aggression. There are major concerns, however, about the ability of the body to maintain thermoregulation leading to heatstroke while taking stimulants. Several deaths in professional athletes have been attributed to their use. Their misuse also can lead to sudden death from cardiac arrhythmias.

Sympathomimetics commonly are used in cold remedies. These include phenylephrine, pseudoephedrine, and synephrine. Their side effects include elevated heart rate, palpitations, anxiety, insomnia, and predisposition to heat illness.

ANTIHISTAMINES

This is another class of medications commonly used in over-the-counter cold remedies and for the treatment of allergies. Their generic names include diphenhydramine, chlorpheniramine, loratadine, cetirizine, and fexofenadine. They have been shown to decrease exercise performance by causing sedation leading to decreased reaction time and performance .  They have no known effect on strength and endurance. For allergies, corticosteroid nasal sprays have been shown to be more affective in controlling nasal allergies without the side effects noted above.

ANTIHYPERTENSIVES

Several different kinds of medications are used to treat high blood pressure. Beta-blockers commonly are used to treat this condition, and their generic names include metoprolol, atenolol, nadolol, and propanolol. These medications have been shown to lower the body’s response to exercise by decreasing heart rate and blood pressure. Studies have shown up to a 15% decrease in aerobic capacity (V˙O_2max) in runners and cyclists. There is no known effect on strength . This class of medication is banned in some sports by the WADA, including the shooting sports, wrestling, skiing/snowboarding, and sailing.

Calcium channel blockers, such as verapamil and diltiazem, also are used to treat high blood pressure. They work much like beta-blockers to decrease the heart rate response to exercise and also can decrease the strength of cardiac contraction.

Diuretics are another common class of high blood pressure medications. They can cause dehydration, leading to an increased risk of developing heat illness .They can cause electrolyte abnormalities, especially low potassium levels, leading to cardiac arrhythmias, as well. They also are banned by WADA because they commonly are used as masking agents in drug screening.

CONCLUSIONS

Medications, whether prescribed by a health provider or taken over the counter, frequently are used. They commonly are taken by athletes and by older individuals who are pursuing an active lifestyle. Medications can have a negative impact on an individual’s training regimen, and health and fitness professionals involved in training clients should be familiar with these effects.