Today's blog intends to dive into flexibility training and Personal
Trainers who use it as a significant component of what they do.
By the end of
this blog, you should have a start point for reading, a new perspective on flexibility
and a few techniques to go away and use.
You should know that as a Personal Trainer, I used to have an
excellent reputation for my assisted stretching skills. These skills helped me
convert members to clients and bring clients in for extra training sessions.
However, when I pushed myself to read more research and
focus on goals, I changed my thoughts on flexibility. Now I rarely use
flexibility training in the form of stretching.
The question must be, why flexibility training? According to
fitness education companies, it was not long ago that stretching was considered
an essential part of the warm-up.
In the UK, the Level 2 Gym Instructor course and the Level 3
Diploma in Personal Training both advocate a mobilisation in the warm-up and
then flexibility training in the cool down.
Flexibility is an essential part of the cooldown for level
3, where the reasons given are as follows –
Stretch appropriate muscles
Appropriate muscles are associated with the range of motion
assessments and postural assessments. So vague, but they do link back to the ACSM,
so what do they say?
More active people are more flexible.
There is nothing else and no reason to do flexibility training,
even though they then give flexibility guidelines. I must mention that they do
hint at posture, but they rule out DOMS. Posture is a whole new blog post.
So even before looking into the research, the primary source
of reasoning for stretching to improve flexibility fails unless the client
personally requests specific stretches for their own reasons.
The visual of a specific muscle stretching comes from a
joint showing more range of motion after a technique than before it, so you see
the bones move further around a joint. So to understand why this happens, it's essential
to understand what blocks the muscle from lengthening.
Due to the wording used, it would be easy to think that the joints
show more range of motion because the muscle physically gets longer. If this were
accurate, then the range of motion would not change if the client was conscious
or unconscious. In the research, the ability for a muscle to stretch is
restricted on a neurological level (unless it is a bone block from the joint),
certainly in the short term. There is little evidence the conscious level does
change the available range of motion, although this evidence is only anecdotal.
I am not saying you should take this as a reason. The feeling of stretch is usually
just the sensation of stretch resistance, which is neurological. PNF stretching
relies on this neurological process.
When measured, the stretch of the muscle seems to happen in
two parts. The slack in the belly of the muscle is used up first. Then the range
is found through the tendon.
The long-term effects of stretching can be an increase in
muscle length. A loaded end range stretch can result in hypertrophy too (just
an aside), but interestingly and in line with the ACSM research, full-range
resistance training also brings on an increase in flexibility.
The only concern with stretching is that the technique could
reduce muscle stiffness, which is vital during some tasks (such as low-intensity
cardiovascular training).
It seems that postural assessments, manual muscle testing,
joint by joint range of motion testing, and then clients own tests, such as sit
and reach, toe touches, etc., seem to be ways that clients or trainers decide
on which muscles or muscles groups to stretch.
As I mentioned earlier, posture is a topic to go into later.
However, I will share with you that when we get to that blog post, it seems
that posture is a better clue to mood than predicting pain or an upcoming
injury!
So I have my conclusion, but please reach your own by
looking at the research I have provided as a jumping-off point to help you find
other papers to read.
My conclusion is that improving flexibility will happen if
you focus on improving motor skills with your client. These exercises will be beneficial
if you use loaded and full-range movements. Stretching techniques do not seem
to be necessary. However, at the end of a training session, the pleasant
feeling of a reduced sense of stretch resistance may be precisely what your
client wants. Since it is difficult to see where stretching has negatives after
a workout, I do not see the problem with stretching to make your client feel
nice. I would do this in the same way as I would put in exercises a client
liked, even if they didn't full link into the fitness outcomes of the client. The
reason for this is that I think the main goal and measure of any training
session should be that the client comes back again.
Book
ACSM's Complete Guide to Fitness & Health Second
Edition Barbara A. Bushman, PhD
Papers
Gleim GW, McHugh MP. Flexibility and its effects on sports
injury and performance. Sports Med. 1997 Nov;24(5):289-99. doi:
10.2165/00007256-199724050-00001. PMID: 9368275.
Simão R, Lemos A, Salles B, Leite T, Oliveira É, Rhea M,
Reis VM. The influence of strength, flexibility, and simultaneous training on
flexibility and strength gains. J Strength Cond Res. 2011 May;25(5):1333-8. doi:
10.1519/JSC.0b013e3181da85bf. PMID: 21386731.
Seymore KD, Domire ZJ, DeVita P, Rider PM, Kulas AS. The
effect of Nordic hamstring strength training on muscle architecture, stiffness,
and strength. Eur J Appl Physiol. 2017 May;117(5):943-953. doi:
10.1007/s00421-017-3583-3. Epub 2017 Mar 9. PMID: 28280975.
Herbert RD, Héroux ME, Diong J, Bilston LE, Gandevia SC,
Lichtwark GA. Changes in the length and three-dimensional orientation of muscle
fascicles and aponeuroses with passive length changes in human gastrocnemius
muscles. J Physiol. 2015 Jan 15;593(2):441-55. doi:
10.1113/jphysiol.2014.279166. Epub 2014 Dec 15. PMID: 25630264; PMCID:
PMC4303388.
Krabak BJ, Laskowski ER, Smith J, Stuart MJ, Wong GY.
Neurophysiologic influences on hamstring flexibility: a pilot study. Clin J
Sport Med. 2001 Oct;11(4):241-6. doi: 10.1097/00042752-200110000-00006. PMID:
11753061.
Nordez A, Gross R, Andrade R, Le Sant G, Freitas S, Ellis R,
McNair PJ, Hug F. Non-Muscular Structures Can Limit the Maximal Joint Range of
Motion during Stretching. Sports Med. 2017 Oct;47(10):1925-1929. doi:
10.1007/s40279-017-0703-5. PMID: 28255938.
Magnusson SP. Passive properties of human skeletal muscle
during stretch maneuvers. A review. Scand J Med Sci Sports. 1998
Apr;8(2):65-77. doi: 10.1111/j.1600-0838.1998.tb00171.x. PMID: 9564710.
Konrad A, Stafilidis S, Tilp M. Effects of acute static,
ballistic, and PNF stretching exercise on the muscle and tendon tissue
properties. Scand J Med Sci Sports. 2017 Oct;27(10):1070-1080. doi:
10.1111/sms.12725. Epub 2016 Jul 1. PMID: 27367916; PMCID: PMC5479471.
Feldman AG. The Relationship Between Postural and Movement
Stability. Adv Exp Med Biol. 2016;957:105-120. doi:
10.1007/978-3-319-47313-0_6. PMID: 28035562.
Steffen K, Nilstad A, Krosshaug T, Pasanen K, Killingmo A,
Bahr R. No association between static and dynamic postural control and ACL
injury risk among female elite handball and football players: a prospective
study of 838 players. Br J Sports Med. 2017 Feb;51(4):253-259. doi:
10.1136/bjsports-2016-097068. PMID: 28148513.
