All Posts tagged Aerobic exercise

Benign Paroxysmal Positional Vertigo (BPPV)

Benign Paroxysmal Positional Vertigo (BPPV)

Feeling dizzy? You Could Have a Vestibular Disorder

Do you experience dizziness? Perhaps when rolling into or over in bed, or turning your head to one side?

Dizziness can be more than dehydration, a big night out, or a compulsion to spin in circles on your office chair. It can be a symptom of asymmetry in your body’s sensory systems.

The most common condition that causes dizziness is benign paroxysmal positional vertigo, or BPPV. The brain has three main mechanisms for perceiving how we interact with the environment around us. These are the visual, proprioceptive, and vestibular systems.

The visual system is self-explanatory. The proprioceptive system is a network of nerves in all of your muscles and joints that relay information about the position of those muscles and joints back to the brain. It is how you can close your eyes and still accurately position your arms and legs in different poses.

The vestibular system is located in your inner ear and is used to identify the position and movement of the head in space. This is the system commonly linked to dizziness and vertigo.

The vestibular system is made up of three perpendicular fluid filled canals in each ear, which relate roughly to the planes of movement.

These canals each have sensory nerves at one end that are made up of crystals resting on fine hairs. When you turn your head, the fluid moves through the canals and pushes on the crystals. This causes the hairs to move and stimulates the nerves.

Your response in each ear should be equal and opposite, and work in tandem with your visual and proprioceptive systems. If things are not working in tandem, then dizziness, vertigo (room spinning), or nausea may result.

Have you ever felt nauseated in a car, or on a boat? This is because your vestibular system recognises that your head is moving but according to your eyes, you are still or moving a different way.

Someone may have suggested looking out the window or finding the horizon. This is great advice as fixating on something which the car or boat is moving relative to, provides a visual reference point and reduces or eliminates the disagreement between the visual and vestibular system.

In patients suffering BPPV, a similar disagreement occurs but it is completely internal. It occurs when crystals in one ear canal become dislodged from the hairs and drift down into the canal. This can happen as a result of trauma but is just as frequently unrelated to any incident.

When the head is turned, the nerve stimulation in one ear is different to the other and a combination of dizziness, vertigo, and nausea can result.

Generally, this resolves in seconds, or in more severe cases last up to two minutes. Usually only one canal will be affected at a time so symptoms are commonly worse to one side, and occur most severely in a single plane of movement.

If you are dizzy due to asymmetry, then your physiotherapist can assess and treat it. Assessment of specific movements can isolate which ear and which canal is causing the problem and treatment involves techniques designed to use gravity and inertia to relocate the crystals back to where they belong at the end of the canal.
NOTE: If you are suffering from severe, sudden onset headache, or persistent dizziness, double vision or nausea that seem unrelated to any particular movement then consult a medical doctor immediately.

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Physical Exercise: The magic bullet for Health

Physical Exercise: The magic bullet for Health

Regular Physical Exercise is the “Magic Bullet”

In an editorial published in the current issue of Cardiology, professors from the Charles E. Schmidt College of Medicine at Florida Atlantic University have evaluated the totality of evidence and conclude that regular physical activity bears the closest resemblance to a “magic bullet” to combat the worldwide epidemic of obesity and cardiovascular disease.

The statistics on regular physical activity in the United States are bleak; only about 20 percent of Americans (23 percent of men and 18 percent of women) engage in recommended levels of regular physical activity and about 64 percent never do any physical activity. In Europe, the statistics are not much better with only 33 percent who engage in physical activity with some regularity, while 42 percent never do any physical activity.

“If regular physical activity were a pill, then perhaps more people would take it,” said Charles H. Hennekens, M.D., Dr.P.H., co-author of the article titled “Regular Physical Activity: A ‘Magic Bullet’ for the Pandemics of Obesity and Cardiovascular Disease,” and the first Sir Richard Doll Professor and senior academic advisor to the dean in FAU’s College of Medicine.

Weight gain as well as being overweight or obese in middle age increase the risk for cardiovascular disease including heart attacks and stroke as well as type 2 diabetes, osteoarthritis and some common and fatal cancers such as colon cancer.

The authors also point out that physical activity confers important beneficial effects beyond body weight and include blood pressure, cholesterol, triglyceride, diabetes, heart attacks, strokes, colon cancer and possibly even breast and prostate cancers as well as arthritis, mood, energy, sleep and sex life.

So with all of these great benefits why don’t people exercise more regularly? The authors suggest that perhaps the time and effort needed for regular physical activity, coupled with the limited accurate knowledge about its immediate and long-term benefits, may contribute to largely sedentary lifestyles. This hypothesis is supported by the survey data from Europe where 42 percent give this as the main reason for their sedentary lifestyle.

“There are a lot of misperceptions about the role of regular physical activity, caloric intake and calories burned during exercise,” said Steven Lewis, Ph.D., co-author and a professor at FAU’s College of Medicine. “And, as a result, calorie restriction dieting has been recommended as more practical for weight control than regular physical activity, and this is a big problem.”

Starting in their 30s, Americans and many Europeans tend to gain between 1 and 3 pounds of body weight per year, and by 55, many are between 30 and 50 pounds overweight. This typical weight gain also is marked by an increase in adipose tissue mass and loss of lean body mass that accompanies an inactive lifestyle.

“Most people have great difficulty achieving and maintaining weight loss solely by restricting their calorie intake,” said Hennekens. “Therefore, modern inactive lifestyles seem to be at least as important as diet in the etiology of obesity.”

The authors note that brisk walking for only 20 minutes a day burns about 700 calories a week, results in a 30 to 40 percent reduced risk of coronary heart disease, and can be performed even by the elderly. They stress that regular physical activity also should include resistance exercise such as lifting weights, which can even be safely performed in the elderly and in patients with heart failure. The maintenance or increase in lean body mass derived from lifting weights promotes an increase in the calories people burn at rest which adds a significant additional contribution to control of body weight.

“The general health benefits of resistance training for middle-aged and older adults are many, including the prevention or limitation of age-related sarcopenia, improved maintenance of muscle mass strength, and a decreased risk of osteoporosis-related bone fractures, falls, physical disability, and mortality,” said Lewis.

Lack of physical activity accounts for 22 percent of coronary heart disease, 22 percent of colon cancer, 18 percent of osteoporotic fractures, 12 percent of diabetes and hypertension, and five percent of breast cancer. Furthermore, physical inactivity accounts for approximately 2.4 percent of U.S. healthcare expenditures or approximately $24 billion a year.

“Clinicians and their patients should remain cognizant of the crucial role of regular physical activity in improving the quality and quantity of life,” said Hennekens. “There also is a need for increased awareness of the importance of resistance training as a valuable adjunct to regular aerobic activity such as brisk walking. And, finally, there is a dire need to educate patients about the importance of regular physical activity for weight control.”

Finally, the authors caution that cardiovascular disease is now the leading killer worldwide and a chief contributor in developing countries, increasing obesity and decreasing levels of physical activity.

Hennekens and Lewis both practice what they preach. Lewis is an exercise physiologist and Hennekens remains an avid tennis player having been the only graduate of Queens College ever inducted into the academic and athletic halls of fame. He also is formerly the No. 4 ranked squash player in the U.S. in the 40 and over division, and was appointed by FAU President John Kelly to serve on the University’s Intercollegiate Athletics Committee.

Journal Reference:
1.Steven F. Lewis, Charles H. Hennekens. Regular Physical Activity: A ‘Magic Bullet’ for the Pandemics of Obesity and Cardiovascular Disease. Cardiology, 2016; 134 (3): 360 DOI: 10.1159/000444785

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Exercise and the Brain: A winning team

Exercise and the Brain: A winning team

“The best way to improve mental performance, is to improve physical performance” – Tim Ferriss¹

So, how does exercise improve learning and memory?Learning requires repeated connection and communication between neurons in a process known as long term potentiation¹.

“Long term potentiation: The strengthening of brain cells’ capacity to send signals across a synapse for the purpose of learning and memory.“ – John Ratey M.D., from ‘Spark’.²

The more repeated this firing across a synapse, the stronger the connection becomes.

“Neurons that fire together, wire together.” – Dr. Daniel Siegel.³

With the example of learning a new language, nerve cells that are recruited in learning a new word will fire a glutamate signal across the synapse.²Without practice, the original synaptic connection will diminish, and the signal will weaken.²The end result, is you’ll forget. On the other hand, regular practice and firing of this new neural connection will strengthen the synapse. The synapse will actually grow in size, and this will improve the ability of the synapse to fire in the future.² And guess what? You’ll remember!

What parts of the brain are involved in memory? One area of the brain that we often read about in terms of memory is the hippocampus.The process of learning, however, involves many more areas of the brain working together.² When the brain receives an incoming stimulus, there is an emotional intensity assigned to it (limbic region), and it is considered amongst past experiences, as well as the social and environmental context, before being formed as a new memory in the hippocampus.The pre-frontal cortex is the decision maker of the brain . It sequences this information, and is able to make a rational decision or judgement about any particular scenario before it settles as a formed memory in the hippocampus.

Coming back to the hippocampus, research has shown that it is particularly vulnerable to degenerative disease.⁴Studies have shown that the hippocampus can literally shrink in size, during the course of degeneration such as dementia.²

The positive, though, is that research has also shown that cardiovacular exercise, as well as routine cognitive challenges (e.g., problem solving, learning a new language) can increase the size of the hippocampus.²

This is another example of neuroplasticity.

Brain-derived neurotrophic factor (BDNF) is crucial for the health of our nervous systems, and it massively increases during cardiovascular exercise.²BDNF is thought to play a really important role in learning, and has been found in lab studies to be present in the hippocampus.²Researchers have found that if BDNF is added to neurons in a petri dish, the neurons sprouted new branches (dendrites), which could be thought of like fertiliser for long term potentiation (learning).²BDNF also helps with synaptic connections, binding to receptors at the synapse and strengthening the neural signal.²

So how much, and what kind of exercise is effective?Unfortunately it still isn’t exactly known what is an ideal type and duration of exercise for improved learning and memory.²

Going by the recommendations of the World Health Organisation⁵, these are guidelines for general health:

Children aged 5-17 years

1.At least 60 minutes of moderate to vigorous intensity physical activity each day.
2.Any extra exercise will provide additional benefits.
3.Should be mostly aerobic exercise. Vigorous-intensity activities should be included, for safe and appropriate muscle strengthening, at least 3 times per week.

Adults aged 18-64 years:

1.At least 150 minutes of moderate-intensity aerobic exercise activity, or at least 75 minutes of vigorous-intensity aerobic activity in one week. (Or a comination of moderate and vigorous intensity activity).
2.Aerobic activity should be at least 10 minutes in duration.
3.For additional health benefits, adults should aim for double the above mentioned recommendation (300 minutes moderate intensity, or 150 minutes of vigorous activity, or combination, per week).
4.Muscle strengthening involving major muscle groups on 2 or more days a week.

Adults aged 65 years and above:

1.At least 150 minutes of moderate-intensity aerobic physical activity, or at least 75 minutes of vigorous-intensity aerobic physical activity throughout the week (or equivalent combination).
2.Aerobic activity should be at least 10 minutes in duration.
3.For additional health benefits, adults should aim for double the above mentioned recommendation (300 minutes moderate intensity, or 150 minutes of vigorous activity, or combination, per week).
4.Balance and falls prevention for older adults with poor mobility, 3 or more days per week.
5.Muscle strengthening involving major muscle groups on 2 or more days a week.
6.When older adults cannot do the recommended amounts of physical activity due to health conditions, they should be as physically active as their abilities and conditions allow.

For anyone being treated for any medical condition, discuss these with your medical practitioner before starting a new exercise program.

For more detailed recommendations, please see the World Health Organisation’s website.

Dr Ratey suggests combining the benefits of cardiovascular exercise (e.g., 60-70% of maximum heart rate) with skill-based, non-aerobic exercise. This will depend on what each person enjoys, and will be able to be consistent with.²

Examples would be tennis, basketball, surfing, or any other activity that challenges both strength, balance, fine motor control, and cardiovascular endurance. This will help challenge and develop different areas of the brain, such as the cerebellum and basal ganglia.

Summary

•Exercise can play an important role in counteracting the neurotoxic effects of prolonged stress.

•Cardiovascular exercise encourages an increase in neurotransmitters, proteins, and hormones that help with neurogenesis and nervous system health.

•Cardiovascular exercise has been shown to considerably improve cognition and long term memory, by strengthening synaptic connections and encouraging neurogenesis (nerve cell growth).

•A combination of strengthening, fine motor skills, and cardiovascular activity seems to be a good way of challenging and developing different areas of the brain.

 

This thoughtful information is brought to you by the excellent website below, please check it out.

http://physiodevelopment.com/cardiovascular-exercise-improving-learning-and-memory/#more-2612

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Shin Splints

Shin Splints

‘Shin Splints’ is an outdated term which is now believed to cover many forms of anterior shin pain. What most people perceive to be ‘shin splints’ should actually be termed Medial Tibial Stress Syndrome (MTSS).

This condition typically presents with pain on the inside border of the Tibia which intensifies at the start of exercise but may ease as running continues in the early stages. Pain generally eases with rest and there are no neurological symptoms. MTSS accounts for approximately 13-17% of running injuries, with only Plantar Fasciitis occurring more frequently. MTSS is 10 times more common in females during basic running training than their male counterparts.

As the name suggests, MTSS is a condition caused by increased bone stress. Even healthy bone contains microcracks, but microcracks under continued overloading will develop into macrocracks, resulting in pain and the potential to develop into Tibial stress fractures if ignored.

How is the Tibia Overloaded?

Our bones are strongest at withstanding compression forces, weaker in tension forces and weakest of all in resisting shearing forces. When we run, all three directions of force are applied to the bone.

Tension Force

When running, the combination of the foot hitting the ground on the outside of the heel and the more medial compression loading force from the Femur onto the Tibia causes a bending force on the bone. The lateral Tibia is subjected to a compression force which as discussed is withstood well, but the medial Tibia undergoes a tension force which can result in bone stress.

There are two reasons why some people are more prone to this condition than others:
◾Those whose Tibia has a narrow diaphyseal width are more prone to bone bending forces
◾Those who overpronate

Overpronation places additional strain on the medial Tibia border due to increased tension in the facial and muscle attachments including the Tibialis Posterior, Soleus and Flexor Digitorum Longus. This ‘pulling force’ increases tensile bone stress on the medial aspect.

Shearing Force

Shearing forces are the hardest on the bone.  These are produced as overpronation at the foot causes an internal rotation force on the Tibia. An external force is placed on the Tibia from above due to external femoral rotation which is made worse by weak hip rotators. This causes a shearing, or twisting force on the Tibia bone.

Treatment

This latest view on MTSS development has some impact on the way the condition should be treated. Treatment should be approached using the following four aims:
◾Strengthen the Tibial cortex and aid recovery
◾Reduce Tensile Tibial bone stress
◾Reduce Shearing Tibial bone stress
◾Reduce vertical loading rate

Strengthen the Tibial Cortex

Bones strengthen in response to stress. But it has to be the right kind of stress and in the right doses. As MTSS is down to too much of the wrong stresses it is vital that the causes which have predisposed the individual to tension and shearing stresses on the Tibial are corrected before commencing a graded running program. So, in the meantime, rest is recommended, from running and walking if this also causes pain.

Graded running programs are designed to gradually overload the bone to strengthen it. Here is an example:
Reduce Bone Stresses

In order to reduce the stress on the Tibia, overpronation must be corrected. It is not simply enough to look at the patient’s feet and determine if they have a ‘good arch’ or not. Even those with a ‘high arch’ can be heavy overpronators! In order to address this properly, gait analysis should be performed using video technology to slow down the running cycle and highlight excess motion at the subtalar joint.

For those found to overpronate, both orthotics and footwear should be addressed. Either stability or motion control shoes should be worn and orthotics inserted in addition, when necessary. Placing orthotics into neutral shoes will be next to useless as the insert will simply ‘sink’ into the cushioning of the shoe.

Overpronation can be further reduced by increasing the range of dorsiflexion available at the ankle. The Gastrocnemius and Soleus muscles are responsible for plantarflexion and so if tight or shortened can reduce the range of dorsiflexion. In order to compensate for this, the foot overpronates further to bring the bodyweight over the stance foot. Stretching exercises and sports massage therapy are ideal for doing this.

Along the same rehabilitation exercise lines, strengthening the lateral rotators of the hip can also help reduce shearing forces on the Tibia. Exercises such as the Clam are ideal.

Whilst it may be a difficult conversation to have, patients who are overweight are more prone to MTSS as the pronation force = mass x acceleration. Higher body mass results in increased pronation.

Reduce Vertical Loading Rate

Finally, the runner, therapist and coaches etc should work together to try to reduce the Vertical Loading Rate (VLR) of the running pattern. What this means is how quickly vertical load is applied during impact. A higher loading rate has been linked to an increased injury risk in runners.

There are a few ways in which this can be achieved but a lot of research is still underway to determine the best ways of doing this. Some will argue for a change in technique to favour forefoot running and others would go as far as recommending barefoot running. Whilst landing on the forefoot rather than the heel does seem to reduce vertical loading rate, it is not clear at the moment the effect that this has on pronation. And so by trying to fix one problem, are we increasing another?

The most effective ways of reducing the VLR, without potentially causing other problems are to:
◾Reduce fatigue
Fatigue is responsible for a decrease in running efficiency and technique, as well as increases in lower limb muscle tension and so bone stress. Fatigue can be reduced using fitness training (cross-training) and correction of training errors.
◾Running form coaching
Working with a running coach can help to improve your running form and make it more efficient, thus reducing energy costs and fatigue.

Conclusion

Researchers and experts in the field of running injuries now believe true ‘shin splints’ to be a result of bone stress to the medial Tibia. With repeated running, the Tibia becomes overloaded, which over stresses the bone. These stresses are caused by excess tension and shearing forces on the Tibia.

Treatment should aim to reduce these forces with rest; footwear or orthotic changes; increases in ankle flexibility and hip rotator strength; weight loss; increased fitness; improved running form and a graded running program to increase cortical bone strength.

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