Stretching: Best before or after Exercise?

Most people know that “warming up” before exercising or playing a sport is important.  But many either skip it, or simply don’t know how to do it effectively.  Historically, static stretching (think of the standard bending, stretching, and long holding of a muscle group in a stretched position) was thought to be the best way to prevent injuries.  However, more and more evidence suggests that it gives no injury prevention benefit, and may actually hinder performance.

A recent systematic review compared nine modern warm-up strategies to a “normal” routine of static stretching.  The results of all of them again were that static stretching doesn't work as well.

In truth, most of us are weekend warriors that don’t have the time or resources to go through vigorous protocols.  We simply want to have fun and try not to get hurt.  My recommendation would be to skip the static stretching.  Instead try starting with some jumping jacks, twisting your torso left and right, or swinging your legs back and forth.  Follow that with about 5-10 minutes of light simulation of whatever you may be doing.  If you’re about to play tennis have an easy rally with your partner while slowly sliding left and right, if you’re about to run then walk or lightly jog the first 1/4 mile, or if you’re playing basketball then shoot the ball a few times and slowly jog to get your own rebounds.  

What’s most important is to get a good amount of blood circulating to your muscles and soft tissues to get them warm and keep them properly nourished.  Once you start to break a bit of a sweat, your core temperature has risen and you’re probably ready.  If there is a place for static stretching, it is probably after the workout is over.  And don’t forget to drink plenty of water too.  

If you have questions or comments, please feel free to  comment below!

Contributed by: Kenneth Q. Hoang, DC

Ice Versus Heat

There is a lot of confusion about when to heat and when to ice an injury or a pain.  While there is no perfect simple answer, here is a good outline to follow.

First, it is important to understand the basic principles 

Ice is used to reduce swelling by causing vasoconstriction (clamping down of the blood vessels in an area).  Heat is used to increase the flow of blood through an area.  Both reduce pain most of the time, but for very different reasons.  Ice shuts off pain signals from an area by effectively turning off the nerve cells due to lack of ability to keep firing in the cold environment.  Heat increases the flow of blood and oxygen, both of which sedate pain fibers.

Of course, if an area gets too cold, it starts to hurt as a message to the brain that tissue damage from cold is about to occur.  With too much heat, as in acute burns, pain fibers are stimulated to initiate a reflex to move away from the source of heat.

In general, our bodies love heat and constantly work to stay warm.  That is why we shiver when we are cold.  Our muscles can generate a lot of heat by contracting repeatedly during shivering.  Bodies also hate to lose heat.  So when we apply ice to an area, the body immediately shuts down the blood flow through that area to reduce the amount of heat loss.  

How can we use this in figuring out whether to use heat or ice?

If there is a new injury that involves any amount of new fresh tissue damage, tearing, over stretching, or anything that can microscopically rip open the tiny capillaries, we want to stop the leaks from occurring by triggering that vasoconstriction effect with ice.  

If there is an muscle that has been working too hard for too long but that hasn’t been damaged or a body area that has been in one cramped position for a length of time, then we want to help it get more blood to replenish the oxygen and nutrient levels.  Also, if there is a body part that is arthritic, heat is very helpful for the same reason of helping to deliver needed oxygen and nutrients and therefore reduce pain.

Ice is best used for about 10 minutes at a time, repeated every 20 minutes.  Longer than 10 minutes can trigger the rescue vasodilation effect, and cause more swelling.  Following a new injury, it is best to use ice during the first 72 hours.  

Heat can be applied for 15 to 20 minutes, at a medium level, as often as desired.  Care must be taken with heating as area above a medium level as that initially shuts off the pain sensors and can result in serious tissue burns.  Also, NEVER bypass the “dead man switch” on heating pads that require you to continually hold down the “on” button.  NEVER sleep on a heating pad.  In either case you run serious risks of major second and third degree burns.  Bad idea. 

What if after all this discussion, you still aren’t sure which way to go?  

When in doubt, use ice.  If you heat an area that should have been iced, it will worsen the swelling and take longer to heal.  If you ice instead of heat, it will make it start to ache more.  No damage will have been done, and you can simply switch to heat and be fine.

Avoiding winter time flu bugs

We all change habits in the winter time, shifting activities indoors due to weather and shorter daylight hours.  Is it a coincidence that the peak flu season is in the mid winter months?  Apparently not.

A very interesting article in Epidemiological Infections covers the history of thinking and investigation about the subject and concludes that there is a very strong correlation with lack of ultraviolet radiation exposure on the skin and incidence of the seasonal flu.  It is well worth reading if for nothing other than an interesting graphic showing a completely inverse relationship to skin UV exposure (and hence Vitamin D production), and the flu.

Our skin synthesizes Vitamin D when exposed to the Sun’s UV radiation, however the Office of Dietary Supplements of the National Institutes of Health point out that the sun screen protection (SPF) we all apply in order to avoid skin cancer (don’t we all use it?) can affect Vitamin D production.  In fact, SPF above 8 completely blocks Vitamin D synthesis.

That said, I advocate using a high SPF sunscreen, generally in the range of an SPF 30 to 50 because it is generally thought to limit UV damage to skin, and hopefully lower our chances of developing skin cancer.  However, since this will significantly reduce Vitamin D production, it is necessary to add a dietary supplement.

A good natural source of Vitamin D is Cod Liver Oil.  However, for those non-fish oil lovers, any off the shelf source of Vitamin D-3 will do.  

While the original recommended daily dose of Vitamin D was 400 iu, the FDA increased to 600-800 iu its recommended daily dose depending on the population age.  The Mayo Clinic article on Vitamin D recommends a maximum safe limit of 10,000 iu.

So, it is not a coincidence that we tend to start getting the winter flu in November, and it peaks in February.  Let’s try to make our Vitamin D levels stable throughout the year and see if we can beat that.

Dementia and low vitamin D levels

Great article by FuturePundit on the link between low vitamin D levels and risk of dementia in old age. Worth a read.

Link Between Cognitive Impairment In Elderly And Vitamin D

Avoiding holiday weight gain

Gaining weight over the holidays—who doesn’t? We socialize more, eat and drink more, and have less time and desire to trek off to the gym. Now that 2013 is right around the corner, it’s time to break those bad habits and get back into a healthy routine. Even if you don’t have time to do your normal exercise, try making an effort to go outside and walk around for 15 to 20 minutes each day.  

A simple 15 to 20 minute walk per day can reduce your risk by up to 1/3 of developing Type ll Diabetes, heart disease, and Alzheimer's disease.  All that for a simple, short, and enjoyable walk.

Have you ever wondered why people used to go caroling?  Perhaps they knew it was a simple way of getting the whole group to be active, socialize a bit, and burn some calories all while having some simple fun. Caroling may not be for all of us, but maybe this year you can think up some fun ways to incorporate exercise into your holiday routine. 

Second helping of turkey? Sounds good! But only once you've danced a few minutes with your partner after that kiss under the mistletoe. Want a slice of pumpkin pie?  No problem.  How about 5 pushups per bite? Add some ice cream?  Sure, but after 10 sit-ups. Want to watch "It's A Wonderful Life" again? Every time the bell rings stand up and walk in place for the next 5 minutes! Get everyone involved, they'll be thankful, too!

Get the idea?  It may not be the most fun you've ever had, but after the holidays are over and your waistline is unchanged or smaller, you will be thanking yourself for months to come.