Stretching is part of every good training program. The problem is that most people don't know much about the science and methodologies of stretching. This blog is to inform you a little more about the types of stretching, when each type should be used, and some other basic tips of how to use stretching in your overall fitness program.
First, let's talk about a why of flexibility and debunking a myth that more flexibility is always better. 'It is possible that flexibility patterns which represent a risk factor for one sport may not do so for another... No clear relationship can be described between flexibility and injury that is applicable to all sports and levels of play. While increased flexibility is important for performance in some sports that rely on extremes of motion for movement, decreased flexibility may actually increase economy of movement in sports which use only the mid-portion of range of movement" (Gleim and McHugh 1997). An example of this would be a runner with some-what tighter calf muscles could be considered advantageous because it would give a more natural spring to each step, which would allow the muscle to not work as hard. An overly flexible calf muscle would have to work harder to produce the same amount of force. So applying this would mean, you should find what movements that you typically do or need to do and you must increase flexibility in muscles holding you back from achieving an adequate range of motion.
Secondly, some different types of streching are:
Dynamic Active Stretching- only using the muscles of the moving body part (i.e. leg/ arm swings).
Static Active Stretching- only using the muscles of the stretched body part to hold a stretched position (i.e. holding your leg in the air as high as possible).
Ballistic Stretching- when you bounce at an extreme range of motion to stretch the muscles, tendons, and ligaments further than otherwise possible. (Not recommended!)
Isometric or PNF Stretching
Static Passive Stretching- using as much external assistance as needed to reach the painless maximum stretch.
Third, let's talk about the when and why some of these types of stretching should be used.
Dynamic Active Stretching is great in the morning to start your day, making you more flexible throughout the day. The purpose of this morning stretch is to reset the nervous regulation of the length of your muscles for the rest of the day. Also it is the main if only type of stretching that is to be done before physical activity. The reason for this being is that unlike Static Passive Stretching it delivers more blood to the muscles continuing to warm them up, in turn helping with flexibility. Also like any physical activity the results are very dependent on speed, angle, intensity, etc., of the exercise. This is call the SAID principle, or Specific Adaptations to Imposed Demands. That being said, to better prepare the body for dynamic movement, dynamic stretching would be an appropriate part of a good warm-up following 5 to 10 minutes of light cardio.
Ballistic Stretching is not recommended anytime! This is not recommended because "ballistic stretches may result in immediate as well as residual pain' the symptom of "minute injury to soft tissue involved in the stretching," which the subsequent strenuous exercises may aggravate ' to the point of serious muscle damage' (Logan and Egstrom 1961) (Thomas Kurz, Stretching Scientifically). When you have so many other types of effective stretching methods, the risks of ballistic stretching just out-weight the rewards.
Finally static stretching, which also in part affects dynamic and static active stretching, is to be done at the end of a workout. This type of stretching is more effective if you are already warmed up. Putting on sweats after your workout before you stretch can help prolong the time your muscles stay warm for stretching. You should hold the necessary stretches for at least 30 seconds each and do these stretches once per day. Try to let your muscles relax here. For example if doing the side splits this would require you to put most of the weight on your arms so the muscles of your legs don't have to contract to support your body weight. As stated before, static stretching should not be performed before dynamic exercise although it is commonly done by others. There are several reasons for this. First, being that performing static stretching before exercise does not necessarily prevent injury. Secondly, it is proven that static stretching reduces the ability to produce force (speed and strength) in the muscles (Fowles etal. 2000). Third, "Reduction of activation, or imbalance in activity, that follows static stretching is more likely to cause an injury than a reduction in strength," (Murphy 1991). Also "If you try to make a fast, dynamic movement immediately after a strenuous stretch, whether static or bouncing, you may injure the stretched muscles," (Thomas Kurz, Stretching Scientifically). So you are starting your workout at a disadvantage. You might run slower, and lift less weight and possibly even injury yourself. This is not conducive to a good training session.