Stretching Techniques: Is Any One Better Than the Other?

Recently I was asked about my level of knowledge on a particular strecthing technique and whether it was better/more effective than the others.  After all of the research I conducted, I came to the conclusion that it all depends on the task in which you are attempting to accomplish.  Below I describe some of the different stretching techniques, how often to do them, and how they are used best.

Active Strecthing:

Active stretching involves using ONLY other muscles to assist in stretching the muscle/muscle group in question.  An example of this would be lying on your back (supine position) and contracting your hip flexors and quad muscles to pull back your leg in order to strech your hamstring muscles.  In this example, the hip flexors and the quads are active (activated and moving) and are aiding in streching the hamstring.  There have been disputes on how long active stretches should be held, but recent research suggests that holding these types of stretches for no longer than two seconds is ideal.  This time frame allows the muscles to optimally lengthen without triggering the protective stretch reflex.  Due to the limited time the muscles are being worked, active stretches are best used when preparing for exercise (warming up).  This is because the activation of the muscles are causing them to warm up but not enough to fatigue the muscle.  It is suggested that you use active stretching techniques previous to any bouts of exercise.  Stretches should be performed in 1-2 sets for 5-10 reps.  Active stretching is not meant to improve flexibility.

Dynamic Stretching:

Dynamic stretching involves using momentum and force to move the muscle through a full range of motion in order to stretch the muscle.  Dynamic stretching is not the same as active stretching given active stretching requires the use of other muscles to stretch the target muscle while dynamic stretching uses forces, i.e momentum and/or gravity, to assist in this process.  Dynamic stretches also do not require you to hold the position while the muscle is being stretched.  A good example of a dynamic stretch is the body weight squat.  This movement uses momentum and gravity when the body goes to a seated position and force production to move the body back to a standing position.  During this movement, the leg muscles are being stretched during the sitting movement and contracted during the act of standing to bring the knees and hips back in line.  Dynamic stretching should be used when preparing for bouts of power generating exercises.  It is recommended that you dynamically stretch the muscle in which you will be using during exercise.  Dynamic stretches should be performed in 1 set for 10 reps using 3-10 exercises per muscle group.  As with active stretches, dynamic stretching is not well suited for increasing flexibility.

Static Stretching:

Static stretching is the technique that most people are aware of.  Static stretching involves the stretching of an isolated muscle group for a period of time, usually 15-30 seconds.  Holding the muscle in a stretch for the specified time frame causes a reflexive action that overrides the protective measures in the muscle that restrict it from stretching further.  Once this override occurs, the muscle is "told" to relax thus allowing it to stretch even further.  Since static stretching causes some muscles to contract for long periods of time which causes muscle fatigue, this technique is not recommended before performing exercise.  Research has shown that static stretching before exercise decreases strength and force production in muscles.  The best time to perform static stretches is after workouts.  This is because muscles are tight from being worked and need to be stretched out to their normal lengths.  Static stretching after exercise and/or during free time helps to eliminate any muscle imbalances that exist and is ideal for increasing flexibility of muscles.  Static stretches should be performed as often as possible (except before exercise or atheletic events) and should be performed in 1-2 sets in which exercises are held for 15-30 seconds (30 seconds is ideal). 

Proprioceptive Neuromuscular Facilitation (PNF) Stretching: 

PNF stretching is a stretching technique that employs the use of resistance during an isometric isolation for a specified timeframe and then muscle relaxation to take the muscle further through its full range of motion.  In other words, putting force on the muscle while it is being stretched to trick it into relaxing therefore causing it to stretch even further.  PNF stretching has been found to be the fastest and most effective way to increase muscle flexibility and range of motion.  If you are trying to improve range of motion and/or flexibility in a short time period, then PNF is the best approach although this technique is mainly used in clinics for rehab purposes.  This is likely because the stretches require help from a partner or the use of an object that can assist you in placing tension on your muscles while stretching.  Since PNF stretching techniques cause fatigue in the muscles, they should be performed after exercise.  There are various techniques in which you can use to stretch your muscles using PNF but I will not go into that much detail as to not bore everyone else.  If you are interested in the different techniques, you will find a good article describing PNF techniques here:

http://www.functionalmovement.com/articles/screening/2010-09-22_proprioceptive_neuromuscular_facilitation_the_foundation_of_functional_training  

Because of the strain that this technique puts on muscles, it is recommended that you allow 48 hours of rest between sessions in which you use PNF and only do it two times per week.  This is to allow adequate time for muscle recovery. 

In my opinion, due to the restrictions and limitations of this technique I would recommend this only to people that are in dire need of becoming flexible in the shortest amount of time possible. Static stretches are more than capable of increasing muscle flexibility and range of motion if performed on a regular basis.  Plus, research has shown that PNF is no more effective than static stretches outside of the fact that PNF has a shorter time period in which effects are seen. 

Make your workout more effective

We now live in an age where work consumes the majority of our time and getting a quick work out in throughout the day is extremely tough.  Even if you are able to squeeze some time in during the day, chances are you have limited time that you can spend in the gym before you have to go back to work or you dont feel like spending that much time in the gym after work.  Plus, if you havent worked out for at least an hour you feel like you havent done enough, right?  Well there is a simple solution to all of this...learn ways to maximize your calorie loss in a shorter period of time.  Below I provide a few tips on how to make your workout more effective in relation to calories burned while spending half of the time in the gym.

-Limit the amount of breaks you take in your workout.  Depending on the type of workout you are doing, limiting the amount of breaks you take during your workout can cut down workout time substantially.  Most breaks between sets should be limited to 60-90 seconds for most endurance and power exercises.  This is the time needed for your body to recover approximately 90% of the energy producing elements in your body.  For maximal strength training, longer breaks are more important but should still be limited to 3-5 minutes between sets. 

-Spending less time on cardio machines.  A lot of us have heard that low intensity exercise in the "fat burning zone" allows us to burn more calories from fat than from proteins and carbohydrates.  This is actually true but knowing this can be misleading.  Although calories from fat are mainly being targeted, it takes a great deal of time to actually burn a decent amount of calories because fats are slow burning fuels that require oxygen to convert it to usable energy.  By performing high intensity training (HIT training), you mainly burn calories from carbohydrates, which are fast burning fuels, but calories from fat are targeted as well.  By doing high intensity training, the total amount of calories burned increases as well as the total number of calories burned from fat solely by volume alone.  Lets look at the comparison:

Calories burned from low intensity workout in 30 min = 300 cal (75% of which is fat calories or 225 cal)           

Calories burned from high intensity workout in 30 min = 620 cal (50% of which is fat calories or 310 cal)

Its obvious that you burn more calories from fat and in general by doing high intensity workouts.  If you want to decrease the time spent on cardio machines, bump up the intensity or the incline to burn more calories.

-Having structured routines.  Having structured workout routines can limit the time you spend in the gym as well.  If you know what you are going to do in the gym beforehand, you wont spend more time in the gym trying to figure out what you want to do next.  Having structured routines also give you the ability to superset exercises or to perform circuit workouts.  By supersetting exercises of the opposite muscle group, you are able to work one muscle group while the other rests and go directly into working the other muscle group while the previously worked muscle rests.  You are able to do two exercises at one time and you are still able to get the required 60-90 second rest between sets.  Circuit workouts are great because they are good for endurance training due to the fact that they limit the amount of rest and keeps your heart rate high for the majority of the workout.  Circuit workouts are intended to be performed at high intensities and therefore require less time to burn more calories.   

GO TO SLEEP!

SLEEP HABITS ARE MORE IMPORTANT THAN YOU THINK!

One of the biggest issues I have as Im sure a lot of you do as well is getting enough sleep given the socially accepted standard of 10-12 hour workdays and having a social/family life on top of that.  Even on days that I got off of work early and I am able to eat dinner by a decent hour, I still have trouble going to bed early due to my sleeping patterns and the fact that going to sleep before 11 makes me feel old.  After doing some research on the effects of not getting enough sleep, I decided that Id rather be healthy than feel cool and youthful.   

Some of the risks associated with getting less than 8 hours of sleep are:

-Learning and memory: Sleep helps the brain commit new information to memory.  Less sleep also affects your alertness which in turn impairs your ability to think and process information. 

-Metabolism and weight: Sleep deprivation can affect the way our bodies process and store carbohydrates.  This can lead to increased weight gain and an altered level of hormones that affect our appetite. 

-Cardiovascular health: Sleep deprivation has been linked to hypertension, irregular heart beat, heart attacks, heart failure, and stroke.

-Long term effects: Psychiatric problems, attention deficit disorder (ADD), fetal and childhood growth retardation (pregnant women), altered immune funtion (which is important for fighting off diseases and sickness), and insomnia. 

Getting the proper amount of sleep also allows the body to recover correctly after bouts of exercise.  The best thing about sleep is that you cant overdose on it.  As long as you get a minimum of 8 hours you can sleep as long as you want.  Ultimately, if you are at home doing something that you dont need to be doing in the late hours of the night...go to sleep.  Whatever it is can wait until tomorrow. 

References: http://www.health.harvard.edu/press_releases/importance_of_sleep_and_health
http://www.webmd.com/sleep-disorders/features/important-sleep-habits?page=2

The science behind crossfit

I have been doing crossfit for about a month now and I have to admit, I am a huge fan.  I usually dont buy into the "fads of the moment" so crossfit was no different initially.  One of my biggest issues with crossfit was that I didnt want to pay the outrageous costs associated with joining a crossfit gym and like every other hardworking adult in the US, work takes up the majority of my time.  Plus, I also figured you needed the special weights and equipment to do it. 

Well, Ill be the first to tell you that crossfit workouts dont take much time at all and if you dont have the equipment, you can always improvise.  For instance, you can use dumbbells in place of kettle bells for any kb workouts.  All in all I would recommend crossfit to anyone that is interested but I will caveat that by saying I also think if you are going to get into crossfit, start off slow regardless of your knowledge of weight lifting.  It is very easy to get injured if you progress too quickly or you are not using the correct form when lifting.

If you are interested in learning the science and reasoning behind crossfit, I highly recommend reading the article attached.  The Science Behind Crossfit