Man : Move It (Physical Exercise)

Physical exercise is a bodily activity that would enhance or maintains physical fitness and the overall health and wellness of a person. 

It is performed for various reasons including 

     a. strengthening of the muscles and 

     b. the cardiovascular system, 

     c. specifically on  athletic skills, 

     d. weight loss or maintenance, 

     e. as well as for the purpose of enjoyment.

Types of exercise

Physical exercises are generally grouped into three types, depending on the overall effect they have on the human body:

i.              Flexibility exercises, such as stretching, improve the range of motion of muscles and joints.

ii.            Aerobic exercises, such as cycling, swimming, walking, skipping rope, rowing, running, hiking      or playing tennis, focus on increasing cardiovascular endurance and fitness

iii.           Anaerobic exercises, such as weight training, functional training, eccentric training or sprinting and high-intensity interval training, it increases the short-term muscle strength.

Categories of physical exercise

               ·         Strength training

               ·         Agility training

               ·         Eccentric training

               ·         Resistance training

               ·         Interval training

               ·         Continuous training

Sometimes the terms 'dynamic' and 'static' are used. 

'Dynamic' exercises such as steady running tend to produce a lowering of the diastolic blood pressure during exercise, due to the improved blood flow. 

Conversely, static exercise (such as weight-lifting) can cause the systolic pressure to rise significantly (during the exercise).

Categories

Physical exercise is used to improve physical skills.

Physical skills fall into the following general categories:

        §  Cardiovascular/respiratory endurance,

        §  Stamina, Strength,

        §  Flexibility, Power,

        §  Speed, Coordination,

        §  Agility,

        §  Balance, and

        §  Accuracy.

Psychological Health effects

Physical exercise is important for maintaining physical fitness and can contribute positively

a.   in maintaining a healthy weight

b.   building and maintaining healthy bone density

c.   muscle strength

d.   joint mobility

e.   promoting physiological well-being

f.    reducing surgical risks, and

g.   Strengthening the immune system.

i. Exercise reduces levels of cortisol, which causes physical and mental health problems.   

ii. Frequent and regular aerobic exercise help to prevent or treat serious and life-threatening chronic conditions such as high blood pressure, obesity, heart disease, Type 2 diabetes, insomnia, and depression.

iii. Endurance exercises before meals lowers blood glucose. Vigorous exercise by a healthy individuals can increase opioid peptides (a.k.a. endorphins, naturally opioids and  other neurotransmitters which are responsible for exercise-induced euphoria, increase testosterone and growth hormone.

iv. Both aerobic and anaerobic exercise is to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training). The exercise are generally beneficial and healthy but not everyone benefits equally from exercise.

Cardiovascular system

Exercise uses up a lot of energy, which the cells derive from oxidizing glucose. Both glucose and oxygen have to be delivered by the blood. The heart has to work harder to pump more blood through the body. The heart beat faster in order to achieve a higher throughput, as described by this equation:

Heart rate for a human being at rest is about 70 beats/min. During vigorous exercise, heart rate can increase dramatically (the rule of thumb given for maximal heart rate is 220 minus your age). This will result in an increase in blood flow.

The blood flow depends very sensitively on the width of the blood vessels, so that changing the radius slightly has a large impact on the flow of blood. 
The circulatory system functions by constricting blood flow of the organs that need less oxygen during exercise and widening the arterioles to the organs which need more. For instance, the brain may use up to 30% of total blood flow while you're doing your homework, but when you're at the gym less than 10% of total blood flow goes through it. On the other hand, muscles use less than 10% of blood flow when at rest, but can take up to 50% of it when they're working. This regulation is an essential mechanism for delivering oxygen and glucose to the tissues that need it most.

A person who modify their behavior after myocardial infarction to include regular exercise have improved rates of survival. ... Persons who remain sedentary have the highest risk for all-cause and cardiovascular disease mortality.

Brain function

A 2008 review of cognitive enrichment therapies (strategies to slow or reverse cognitive decline) concluded that "physical activity and aerobic exercise in particular, enhances older adults' cognitive function".

Exercise affects the brain on multiple fronts. It increases heart rate, which pumps more oxygen to the brain. It also aids the bodily release of a plethora of hormones, all of which participate in aiding and providing a nourishing environment for the growth of brain cells.

Exercise stimulates the brain plasticity by stimulating growth of new connections between cells in a wide array of important cortical areas of the brain. 

From a behavioral perspective, the same antidepressant-like effects associated with "runner's high" found in humans is associated with a drop in stress hormones. A study from Stockholm  showed that the antidepressant effect of running was also associated with more cell growth in the hippocampus, an area of the brain responsible for learning and memory.

In addition, physical activity has been shown to be neuroprotective in many neurodegenerative and neuromuscular diseases. For instance, it reduces the risk of developing dementia. Furthermore, anecdotal evidence suggests that frequent exercise may reverse alcohol-induced brain damage.

There are several possibilities for why exercise is beneficial for the brain. Examples are as follows:

• increasing the blood and oxygen flow to the brain
• increasing growth factors that help create new nerve cells
• increasing chemicals in the brain that help cognition such as dopamine, glutamate  and seretonin. 

Physical activity is thought to have other beneficial effects related to cognition as it increases levels of nerve growth factors, which support the survival and growth of a number of neuronal cells.

Exercise's Effects on Bones and Muscles

Exercise is critical for strong muscles and bones. Muscle strength declines as people age, but studies report that when people exercise they are stronger and leaner than others in their age group.

Exercise may help kids lower their risk of chronic pain in the future.

a.    Bone Formation

Bones are comprised of calcium, phosphorous, sodium and protein collagen. When you engage in a high-impact activity, such as running, each time your foot hits the ground, your entire skeleton acts as a shock absorber. This transmits signals to your bones, resulting in new bone formation. Low-impact exercise, such as walking, allows for new bone formation, just not as fast.

b.   Increased Synovial Fluid

A joint is formed where two bones connect. As your joints move when exercising, there is an increase in synovial fluid. Synovial fluid is found on the smooth cartilage inside the capsule of the joint. The more you move the more synovial fluid your body produces --- lubricating your joints, helping you move easily and increasing your range of motion when exercising.

c.       Muscle Fiber Tears

Each muscle is made up of thousands of muscle fibers. Muscle fibers pull against each other during movement or a muscle contraction. Depending on the level of activity, you may feel sore following a workout. For example, when weightlifting, there is more force, causing more pressure on your muscle fibers. This results in microscopic tearing of the fibers. With rest, your body heals, resulting in increased strength and muscle size.

The short-term effects of exercise on your muscles and bones help your body adapt to the level of activity you are engaging in, whether you're weightlifting, swimming or running. From your head to your toes, you have 206 bones providing support to your body. Your bones don't work alone during exercise, however --- your muscles are necessary for movement, pulling on your bones when you move.

Ways exercise can improve your life.

  i.      Exercise controls weight

Exercise can help prevent excess weight gain or help maintain weight loss. When engaging in physical activity, you burn calories. The more intense the activity, the more calories burnt. To reap weight-loss benefits doesn’t need to set aside large chunks of time for exercise. Get more active throughout the day in simple ways — by taking the stairs instead of the elevator or revving up your household chores.

ii.         Exercise combats health conditions and diseases

No matter what your current weight, being active boosts high-density lipoprotein (HDL), or "good," cholesterol and decreases unhealthy triglycerides. Exercises keeps your blood flowing smoothly, which decreases risk of cardiovascular diseases. In fact, regular physical activity can help prevent or manage a wide range of health problems and concerns, including stroke, metabolic syndrome, type 2 diabetes, depression, and certain types of cancer, arthritis and falls.

iii.      Exercise improves mood

A workout at the gym or a brisk 30-minute walk can help emotional lift and let off stressful days. Physical activity stimulates various brain chemicals that may leave you feeling happier and more relaxed. You may also feel better about your appearance and yourself when you exercise regularly, which can boost your confidence and improve your self-esteem.

iv.      Exercise boosts energy

Regular physical activity can improve your muscle strength and boost your endurance. Exercise and physical activity deliver oxygen and nutrients to your tissues and help your cardiovascular system work more efficiently. And when your heart and lungs work more efficiently, you have more energy to go about your daily chores

v.         Exercise promotes better sleep

Regular physical activity can help to fall asleep faster and deepen sleep. Just don't exercise too close to bedtime, or you may be too energized to fall asleep.

vi.      Exercise puts the spark back into your sex life

Regular physical activity can leave you feeling energized and looking better, which may have a positive effect on sex life. Regular physical activity can lead to enhanced arousal for women. And men who exercise regularly are less likely to have problems with erectile dysfunction than are men who don't exercise.

vii.      Exercise can be fun

Exercise and physical activity can be a fun way to spend some time. It gives you a chance to unwind, enjoy the outdoors or simply engage in activities that make you happy. Physical activity can also help you connect with family or friends in a fun social setting. So, take the hiking trails or join a soccer team. Find a physical activity you enjoy, and just do it. If you get bored, try something new.

Exercise and physical activity are a great way to feel better, gain health benefits and have fun. 
As a general goal, aim for at least 30 minutes of physical activity every day. To lose weight or meet specific fitness goals, you may need to exercise more. Remember to check with your doctor before starting a new exercise program, especially if you have any health concerns.

Barriers to fitness: Overcoming common challenges

Sticking to a regular exercise schedule isn't easy. Get practical tips for overcoming common barriers. There are plenty of potential hindrances — time, boredom, injuries, self-confidence. But these issues don't need to stand in your way. Consider practical strategies for overcoming common barriers to fitness.

a.   Don't have enough time to exercise

Setting aside time to exercise can be a challenge. Use a little creativity to get the most out of your time.

• Squeeze in short walks throughout the day. If you don't have time for a full workout, don't sweat it. Shorter spurts of exercise, such as 10 minutes of walking spaced throughout the day, offer benefits too.
• Get up earlier. If your days are packed and the evening hours are just as hectic, get up 30 minutes earlier twice a week to exercise. Once you've adjusted to early-morning workouts, add another day or two to the routine.
• Drive less, walk more. Park in the back row of the parking lot or even a few blocks away and walk to your destination.
• Revamp your rituals. Your weekly Saturday matinee with the kids or your best friend could be reborn as your weekly Saturday bike ride, rock-climbing lesson or trip to the pool.

b.   Exercise is boring

It's natural to grow weary of a repetitive workout day after day, especially when you're going it alone. But exercise doesn't have to be boring.

• Choose activities you enjoy. You'll be more likely to stay interested. Remember, anything that gets you moving counts.
• Vary the routine. Rotate among several activities — such as walking, swimming and cycling — to keep you on your toes while conditioning different muscle groups.
• Join forces. Exercise with friends, relatives, neighbors or co-workers. You'll enjoy the camaraderie and the encouragement of the group.
• Explore new options. Learn new skills while getting in a workout. Check out exercise classes or sports leagues at a recreation center or health club.

c.    Self-conscious about look

Don't get down on yourself! Remind yourself what a great favor you're doing for your cardiovascular health, or focus on how much stronger you feel after a workout.

• Avoid the crowd. If you're uncomfortable exercising around others, go solo at first. Try an exercise video or an activity-oriented video game. Or consider investing in a stationary bicycle, treadmill, stair-climbing machine or other piece of home exercise equipment.
• Focus on the future. Praise yourself for making a commitment to your health. And remember that as you become fitter and more comfortable exercising, your self-confidence is likely to improve as well.

d.   Too tired to exercise after work

Breaking the cycle with physical activity is one of the best gifts you can give yourself.

• Try a morning dose of exercise. Get up 30 minutes earlier to exercise, hop on the treadmill or stationary bicycle while you listen to the radio or watch the morning news. Or step outside for a brisk walk.
• Make lunchtime count. Keep a pair of walking shoes at your desk, and take a brisk walk during your lunch break.
• Be prepared. Put workout clothes on top of your dresser, socks and all. Keep a full water bottle in the fridge. Have an exercise video queued up and ready to go when you get home at night.
• Hit the hay earlier. Running on empty is no way to face a full day. Go to bed earlier to make sure you're getting enough sleep.

e.   Too lazy to exercise

If the mere thought of a morning jog makes you tired, try these thoughts on for size:

• Set realistic expectations. Don’t set your expectation too high, you might give up without even trying. Start with a walk around the block. Don't give up if you feel worn out. Take another walk around the block tomorrow. Keep it up, and eventually you'll no longer feel worn out.
• Work with your nature, not against it. Plan physical activity for times of the day when you tend to feel more energetic — or at least not quite so lazy.
• Schedule exercise as you would schedule an important appointment. Block off times for physical activity, and make sure your friends and family are aware of your commitment. Ask for their encouragement and support.

f.     Not athletic enough

Natural athletic ability isn't a prerequisite to physical activity.

• Keep it simple. Try something basic, such as a daily walk.
• Start a team. Join up with friends who are in the same boat. And have fun while helping each other work out.
• Forget the competition. Don't worry about becoming a superstar athlete or joining the hard-bodied athletes at the fitness club. Simply focus on the positive changes you're making to your body and mind.

g.   Tried to exercise in the past but failed

Don't throw in the towel. You can't see it when you lower your cholesterol or reduce your risk of diabetes, but that doesn't mean you aren't doing yourself a great favor. Re-evaluate what went wrong, and learn from your mistakes.

• Pace yourself. Start small and build up to more-intense workouts later, when your body is ready.
• Set realistic goals. Don't promise yourself you're going to work out for an hour every day, and then get down on yourself when you fall short. Stick with goals you can more easily achieve, such as exercising 20 minutes a day, three days a week for the first month.
• Remember why you're exercising. Use your personal fitness goals as motivation — and reward yourself as you meet your goals.

h.   Can't afford health club fees

You don't need a membership at an elite gym to get a great workout. Consider common-sense alternatives.

• Do strengthening exercises at home. Use inexpensive resistance bands — lengths of elastic tubing that come in varying strengths — in place of weights. Lift plastic milk jugs partially filled with water or sand. Do push-ups or squats using your body weight.
• Watch an exercise video. Try videos on dance aerobics, cardio-kickboxing, yoga or Tai chi. For variety, trade exercise videos with a friend.
• Start a walking group. Round up friends, neighbors or co-workers for regular group walks. Plan routes through your neighborhood or near your workplace, along local parks and trails, or in a nearby shopping mall.
• Take the stairs. Skip the elevator when you can. Better yet, make climbing stairs a workout in itself.
• Try your community center. Exercise classes offered through a local recreation department or community education group might fit your budget better than an annual gym membership.

i.     Afraid will hurt myself if exercise

If you're nervous about injuring yourself, start off on the right foot.

• Take it slow. Start with a simple walking program. As you become more confident in your abilities, add new activities to your routine.
• Try an exercise class for beginners. You'll learn the basics by starting from scratch.
• Get professional help. Get a fitness tutorial from a certified expert, who can monitor your movements and point you in the right direction. If you've had a previous injury, you may want to first see a sports medicine physician, who can evaluate you and recommend specific treatment, such as physical therapy.

j.     My family doesn't support my efforts

Remind those close to you of the benefits of regular exercise — and then bring them along for the ride.

• Get started with your kids. Sign up for a parent-child exercise class. Pack a picnic lunch and take your family to the park for a game of tag or kickball. Splash with the kids in the pool instead of watching from your chair.
• Propose a new adventure. Instead of suggesting a workout at the gym, invite a friend to go to an indoor climbing wall or rent a tandem bicycle for the weekend.
• Do double duty. Volunteer to drive your teens to the mall, and then walk laps inside while you wait for the shoppers. Try the same trick at your child's school during lessons, practices or rehearsals.

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Excerpt with thanks from:

www.livestrong.com/article/481516-short-term-effects-on-bones-muscles-during-exercise/

Mayo Clinic staff

Wikipedia