Lon Kilgore wrote in ‘The Paradox of the Aerobic Fitness Prescription” (Crossfit journal) that improvements in oxygen management could be driven by dropping Oxygen saturation during/after exercise. The logic of the General Adaption Syndrome (Seyle) requires an alarm phase to provoke adaptations.
“In the intermediate trainee and beyond, it is the depression of oxygen saturation as a result of interval training that forces the muscle to adapt to improve its ability to extract and consume oxygen to power exercise. Oxygen saturation is a marker of the specific driving force of VO2max gain*. If a beginner does long-slow-distance work and blood oxygen saturations drop 1% or less to 97%, this is enough to drive adaptation. But intermediate, advanced, and elite trainees need more. They need a drop in oxygen saturation to as low as 91%, maybe even lower for an elite athlete”
This observation was supported by David Lin et al who wrote “Oxygen saturations and heart rate during exercise performance” There is a fascinating write up here This basically showed that at a certain level of work, you can see a drop in O2 saturations
“SpO2% desaturations during maximal performance levels with power bursts into the clusters as revealed in this test could lead to measures of intense interval training providing an important augmentation to sports conditioning. “
This mornings workout was a 15 minute AMRAP of 20 kettlebell swings, 15 double unders 150m sprint . I decided today, I’d take my pulse oximeter down. About half way through, straight after my double unders and during the run I managed to get my pulse ox on and this reading came up.
After a quick recovery our workouts always end with a disgusting stair climb to our flat ( to get home and haul the kettlebells back up) At the top it always feels as if you are going to die. As I reached the top I managed to get my pulse ox back on and whilst my heart rate was 160, my O2 saturations were 97. It took me a while to get my phone out so I only got a photo after my heart rate had dropped to 152
My take home conclusion is that the variation in a Crossfit workout combined with power (in his case jumping in the double unders) really stresses the oxygen system. The requirement to rapidly change from one exercise to another takes the body by surprise and has it scrabbling around for oxygen like a pandemic government trying to buy PPE. BY comparison the rhythmic stair climb. which felt disgusting, and produced a highish heart rate, didn’t disturb my normal reading of 97%.
Obviously this is an old Pulse oxmimeter, this wasn’t a clinical environment ( no lab rats, no one had a clip board), but it was an in treating bit of citizen science!)
If you have never heard of it *According to wikipedia “Oxygen saturation is the fraction of oxygen-saturated hemoglobin relative to total hemoglobin (unsaturated + saturated) in the blood. The human body requires and regulates a very precise and specific balance of oxygen in the blood. Normal arterial blood oxygen saturation levels in humans are 95–100 percent”
The answer to this seemingly obvious question is often confused by trying to define what fat and fit means.
Over the years the measurement of fat and indeed its distribution has raised some interesting questions. I’m very aware of the muscular athletic awesome looking athlete who comes back from their annual medical having been told they are obese according to their BMI. These are people, who when their body fat is checked (using callipers or some sort of science fiction machine) are down into the enviable category!
The next interesting “quickie” fat measure came when the discussion of abdominal obesity became fashionable the waist to hip ratio measurement was quick and easy and it certainly measured the tummy fat that showed.
Today, we should all be about visceral fat. But, It’s a hard thing to measure without a CT scan . The problem with visceral fat (the fat inside your visceral cavity, or around your organs) , is that skinny people can have visceral fat and that people with a big tummy don’t necessarily have visceral fat. It can sometimes be all subcutaneous!
Basically we have obvious fat and visceral fat.
Now we need to ask what is healthy or what is metabolically unhealthy According to Ortega (2012) . If you crave the “metabolically unhealthy” crown, you must have one or more of these readings
high blood pressure (≥130/85 mmHg)
high blood triglycerides (≥150 mg/dL)
low HDL “good” cholesterol (<40 and 50 mg/dL in men and women, respectively)
high fasting blood sugar level (≥100 mg/dL)
Since the NHS actually started recording the prevalence of obesity it was correlated with high blood pressure, high triglycerides, low good cholesterol and poor blood sugar. So it was quickly assumed that any overweight person would have these metabolically unhealthy markers. It wasn’t difficult to imagine the step to saying obesity causes them.
However, this is a great example that causation doesn’t necessarily mean causation. Is it possible to be visibly overweight ( I know that’s terribly subjective, but work with me) but still have metabolically healthy readings ( good blood pressure, good blood sugar).
Ortega et al wrote ”The intriguing metabolically healthy but obese phenotype: cardiovascular prognosis and role of fitness ”
They ran some tests using BMI and the 4 health markers and noted (i) metabolically healthy but obese individuals have a higher fitness level than their metabolically abnormal and obese peers; (ii) after accounting for fitness, metabolically healthy but obese phenotype is a benign condition, in terms of cardiovascular disease and mortality. this led to these conclusions (i) Higher fitness should be considered a characteristic of metabolically healthy but obese phenotype. (ii) Once fitness is accounted for, the metabolically healthy but obese phenotype is a benign condition, with a better prognosis for mortality and morbidity than metabolically abnormal obese individuals.
“Metabolically healthy” obese participants had a better baseline fitness level on the treadmill test compared with “metabolically abnormal” obese participants (adjusting for age, sex, examination year, smoking and alcohol consumption, and when using either BMI or body fat percentage to define obesity). The difference was the same for men and women.
“Metabolically abnormal” obese participants had significantly increased risk of dying from any cause during follow-up compared with “metabolically healthy” obese participants (adjusting for confounders and using either BMI or body fat percentage to define obesity).
When looking at cardiovascular disease outcomes, “metabolically abnormal” obese participants only had increased risk of a fatal or non-fatal cardiovascular disease event compared with “metabolically healthy” obese participants when using body fat percentage to define obesity. There was no difference in risk when using standard BMI definitions.
“Metabolically healthy” obese participants had no difference in risk of dying from any cause, or of fatal or non-fatal cardiovascular disease events compared with “metabolically healthy” normal-weight or fat participants.
On a narrow set of health criteria and dubious “obesity’ assessments it’s quite possible to argue that you can be fat and fit! However, over the years more concern has been raised about where your fat is . Research has indicated,visceral fat may be doing something far more nasty.
“Visceral Fat Adipokine Secretion Is Associated With Systemic Inflammation in Obese Humans” 2007 concluded “that visceral fat is an important site for IL-6 secretion ( an inflammation causing thing) and provide a potential mechanistic link between visceral fat and systemic inflammation in people with abdominal obesity”. So there is an interesting line of experiments that indicate that visceral fat could be there, releasing nasty stuff.
The interesting thing is that you can be quite skinny and still have visceral fat and you can be obese and have no visceral fat. So based on some current evidence and where you fat is you can be both visibly fat and fit and skinny and ill!
(Update added 4th August 2020) However, it seems that science gallops on on! There are an increasing number of reports that suggest any sort of obesity is bad for your health. The above article looked at the narrow proposition that you can have “markers” of fitness and still be overweight. The clear answer is yes.
However there are other markers. Things like Adipokines, (which can be either pro or anti inflammatory ) It seems that the fatter you are, the more pro inflammatory they become. Which is bad.
So watch out for the next article in this series that will probably be “Can you be fat and healthy”
I’m not really that into navel gazing. I came from a religious family so I’ve had my fill of sitting quietly. On top of my christian praying and reflecting experience, my mother and brother even fell for that 1970’s transcendental meditation craze. So I had to put up with that too. Being 14 and being made to meditate wasn’t fun.
Never the less there are some lessons to be learned from “sitting with yourself” or as Socrates said, “the unexamined life is not worth living”. To sensibly ask yourself questions is actually a good idea. To actually listen to the answers is probably better!!
So you’ve decided, once again to lose weight. This time, rather than just jumping on the first weird diet you can think of, why not ask yourself some questions. Here are some useful ones.
Spend a bit of time thinking about the past ( both recent and longer term). Not too much, otherwise you can lose yourself in the mists of time. But get a handle of your history.
Are you overweight now?
Why are you overweight? (This is a very stark, rude question, but was it illness, unhealthy eating, too much food, not enough exercise etc).
Have you ever lost weight before?
If so, what helped?
and what hindered?
Ok, so you have lost weight in the past! What made you put the weight back on?
Ok, thats your past, or as much as you realistically need to consider, what are your views and targets now?
Are you looking for a short term fix (a wedding in 2 weeks), or are you prepared to have a long term target
To be successful you need to change your approach to food, weigh and measure, change choices, record your eating habits, and exercise, and all this will no doubt make you feel uncomfortable. So, on a scale of 1 to 10 (10 is high) answer these questions.
Be honest, as we can all want to lose weight but not have much motivation because we know it’s hard work?
How motivated are you to lose weight?
How motivated are you to change your eating habits?
How motivated are you to increase your physical activity?
Will you try new strategies/techniques for changing your eating, exercise, and other behaviours?
Are you prepared to spend time studying reading materials about nutrition ?
Will you record your exercise and everything you eat and drink,?
Will you change your eating habits?
Will you be able to work regular physical activity into your daily schedule?
Will you be able to exercise and be active most, if not everyday?.
If you make a mistake, have a lazy day, or give into temptation, can you forgive yourself, and “get back on the programme”?
Do you have an emotional connection with food?
Do you eat more when you are upset, annoyed or miserable?
Do you eat to celebrate?
If you have confrontation, do you seek comfort in food to calm down?
A SERIOUS BIT
Think about this question carefully?
Have you ever purged (used laxatives, diuretics, or vomiting) to control your weight?
If yes, is this “often” (About once a month A few times a month About once a week About three times a week Daily.)
If purging is part of your present weight loss strategy, and you feel unable to stop, you probably need to chat to your doctor who could get you some one to one support to deal with this issue
Thats just the tip of the iceberg. If you’d like more help or thoughts on managing your weight, do join the mailing list of email me directly on Andrew@andrewstemer.com
Try and do the foot exercises below. Your feet will love you, and you will also learn to love your feet. This type of activities are also helpful in your battle against plantar fasciitis.
Scrunch your toes, with or without a towel. Just think about the position you leave them in normally. Straight and locked in your shoes like prisoners. To paraphrase Marie Antoinette “Let them scrunch air” or treat them to a scrunch festival on a towel! Give them some manoeuvering room.
Splay your toes: see if you can splay them.
It was a bit of a battle for me to learn how to do this ( as, like you I’ve locked my feet into shoes for the last years, so I alternate the splay with using my fingers to pull them apart ( you can do it en-mass as shown here or individually )
Big Toe stretch
Slowly stretch and pull the toe backward toward your shin. Go as far as is comfortable.
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Among a batch of reports studying the Crossfit method, you’ll find “physiological Predictors of Competition Performance athletes” by Martinez-Gomez et al worth a read ( or a quick skim).
In reality any attempt to predict an athletes performance in a specific wod is always a bit speculative as different wod’s can have massively different outputs and can focus on specific “modal domains”that can bring specialists to their knees. Wod’s can be as wide ranging as “run 5k” or “deadlift 1,1,1,1,1,1,1”.
Nevertheless this study took the 5 wods of the Crossfit Open in 2019 and evaluated the performance of 15 athletes who were also assessed against various laboratory tests: incremental load test for deep full squat and bench press; squat, countermovement and drop jump tests; and incremental running and Wingate tests. It would be a fairly safe bet to say that the athlete who scores high on all of these tests would also score highly in the Wod’s.
In 2019 the “open” wods were
19.1 Complete as many rounds as possible in 15 minutes of
19 wall-ball shots
19.2 Beginning on an 8-minute clock, complete as many reps as possible of:
15 squat cleans, 135 / 85 lb.
13 squat cleans, 185 / 115 lb.
If completed before 8 minutes, add 4 minutes to the clock and proceed to:
11 squat cleans, 225 / 145 lb.
If completed before 12 minutes, add 4 minutes to the clock and proceed to:
9 squat cleans, 275 / 175 lb.
If completed before 16 minutes, add 4 minutes to the clock and proceed to:
7 squat cleans, 315 / 205 lb.
19.3 For time:
200-ft. dumbbell overhead lunge
50 dumbbell box step-ups
50 strict handstand push-ups
200-ft. handstand walk
Men 50-lb. dumbbell / 24-in. box Women 35-lb. dumbbell / 20-in. box
For total time:
3 rounds of:
12 bar-facing burpees
Rest 3 minutes
Then, 3 rounds of:
10 bar muscle-ups
12 bar-facing burpees
Men 95 lb. Women 65 lb.
33-27-21-15-9 reps for time of:
Men 95 lb. Women 65 lb.
“CrossFit performance (i.e., final ranking considering the sum of all WODs, as assessed by number of repetitions, time spent in exercises or weight lifted) was significantly related to jump ability, mean and peak power output during the Wingate test, relative maximum strength for the deep full squat and the bench press, and maximum oxygen uptake (VO2max) and speed during the incremental test”. However the relationship varied depending on the wod analysed. No surprise there.
Interest in military fitness regimes has also been stoked up by books such as “Can’t Hurt Me” by David Goggins and our relentless diet of war films.
Having been involved in the training of a few wannabe participants, chatted to a contestant who got a good way through the process, and having analysed the challenges, I thought it would be helpful to offer some general training and preparation advice.
I have a motto, stolen from an ancient greek warrior. In a crisis, you do not rise to the challenge, you sink to the level of your training. Success in these types of programs , and indeed success in applying for a position in the army, and their elite corps, requires you to be properly trained for the challenges you can anticipate.
Lower down in this article you find details of how military fitness testing goes, and the standards they expect. However, here is your take home message. To successfully survive one of these regimes, I say you need a good back ground in being “outdoors”. Do you love going for hikes in the rain and getting soaked. Do you know how to manage wet clothing. Are you ok with sleeping outside, and essentially are you ok with operating on limited sleep and getting up at 2, 3am and going for a run. Do you love camping. Would you turn down some super sex for a 10k run?
If your preparation only involves going to the gym, at sociable times, the chances are you’ll be screwed.
Let me rephrase this. You need to be able to put up with crap they don’t even have names for. Are you used to insect bites, going for a pooh in a bush, stinking and running in boots. Have you had blisters on your blisters, and can you work through the discomfort of a wet pant band working their way into your crotch.
Do you like the cold? Well you better like those morning cold showers and going out in all sorts of weather. On the plus side, getting used to the cold has benefits. A few years ago, “Thermal loading” was all the rage!
There is another type of training you should consider. It’s mindset. Doing a lot of mindset work would probably help; learning how to break big tasks into little task: it may be 4 am in the morning, you may have run 8 miles, you may be at the end of your tether but, maybe you can get to that tree thats 50m away. Ok, now let’s try that house 40m away. Not letting the enormity of the task overwhelm you is important.
This involves dealing with fear The science fiction fans amoung you will recall this monologue from Dune
“I must not fear. Fear is the mind-killer. Fear is the little-death that brings total obliteration. I will face my fear. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the fear has gone there will be nothing. Only I will remain.”
To be successful you probably need to distinguish the difference between fear and recognising danger. Fear is often described as False Evidence Appearing Real. Fear is an impractical emotion. Recognising danger and taking appropriate action is good. Being paralysed by fear, isn’t.
Lord Moran, ( Winston Churchill’s physician, and a trench doctor in WW1) said “Courage is a moral quality; it is not a chance gift of nature like an aptitude for games. It is a cold choice between two alternatives, the fixed resolve not to quit; an act of renunciation which must be made not once but many times by the power of the will. Courage is willpower.” (The Anatomy of Courage).
This is part of working out how you think . Are you already looking for your excuse, or are you thinking, “I’m going to give this 100%”. Having a victim mentality can quickly bring your performance to an end. Combating a perfectionist mindset is also part of the magic. You’ll be slower and feel like you cannot succeed. Ignore that and just continue.
It’s worth remembering that 90% fail (the real) SAS selection, and most of these simply give up. The instructors rarely have to fail people.
The last thing you need to prepare for is lack of sleep. This is truly awful. Here are the consequences of not sleeping (Ref):
Humans can bear several days of continuous sleeplessness, but it screws everything. It may lead to deteriorated functioning, impaired perception, reducing concentration, vision disturbances, slower reactions, as well as lower capabilities and efficiency of task performance and to an increased number of errors.
It screws with your thinking which means wrong decisions, and emotional disturbances such as deteriorated interpersonal responses and increased aggressiveness.
Being woken up at 2 am to do a run or burpees is really, really awful. It is however a reality that soldiers at times need to operate in a sleep deprived state. There are some interesting tips and hints here but, it seems that you’ll need to set yourself some middle of the night exercise sessions. “Exposing soldiers to fatigue in a training environment teaches them how it affects them and their performance. Learning the consequences in a protected environment will help them identify the issues caused by sleep deprivation, so that they can know how deal with them before reaching combat. Likewise, understanding why you’re tired can help you power through the day”(National Sleep Foundation)
If you are from a farming background, you probably have some experience of sleep disturbing work like lambing, milking and chasing poachers. I knew a financial broker who got up to trade at 3am. I think after a few years he went a bit mad: but that could have been the drugs and the booze.
David Goggins, the navy seal, suggested an interesting task. It’s called a 4x4x48. In other words you go for a 4 mile run every 4 hours for 48 hours. That will give you a very good idea of what sleep deprivation feels like, although, I’d start at something like 2 x 4 x 12, and build up!
So, thats the background . What follows are the physical tests along with some official guidance from the military like this US Navy Seal training guide. Download and read it. Its free and useful
With these points in mind, you need to prepare for the actual standards. Either you have the knowledge to develop an effective training regime to master these, or you need a PT /or a coach
4km loaded march with 40kg within 50mins followed by 2km with 25kg in 15 mins (Infantry/RAC). The times allowed for 16 AAB/Paras are shortened to 35mins and 12.30mins respectively.
Fire and movement tactical bounds, followed by crawl and sprint ( 20 x 7.5 m bounds , or mini sprints. Then crawl 15m, sprint 15 m in 55 seconds
Casualty drag (110kg bag) dragged 20m in 55 seconds
Water can carry (simulates stretcher carry with 2 x 22kg cans) over 240 meters in 2 mins.
Vehicle casevac (70kg lift with 3 second hold)
Repeated lift & carry (20kg bags over distance) 20 x 30m in 14 minutes
I say you should not only be familiar with these challenges. You should do them, often, as part of your training. I think you should see these as the absolute minimum standards. Whilst I’m not sure, I’d prepare to do these tests with boots on.
The Royal Marines’ Pre-Joining Fitness Test allegedly involves completing two 2.4km runs on a treadmill that is set to a 2% incline. The first run must be completed in less than 12 minutes 30 seconds. You will then have a one-minute break before completing the second run in under 10 minutes and 30 seconds. This time is the absolute minimum requirement, and the expectation is that you will record the best time possible. You can use this chart to assess where you are
There are 4 body weight challenges. You should aim to ace them all. Why would you humiliate yourself on TV if you can only do 10 push ups if you know that 60 is the standard.
The VO2 Max bleep test (also known as the ‘bleep test’.) Minimum pass score is level 10.5. Shoot for the max!
Press ups are carried out immediately after the bleep test. A maximum score is achieved for 60 press-ups are conducted to an audible bleep (listen to the video below). Arms should be locked into side, shoulder width apart. The partner puts his fist on the floor facing away and counts one repetition for every time the chest touches his fist. If you put your knees onto the floor you will be told to stop.
Sit-ups come straight after the press-ups. 85 are needed for maximum points. Sit ups are conducted to an audible bleep. A partner holds the feet, elbows must touch top of knees and then the shoulders and elbows must touch the floor on the way down for a repetition to count. Knees must remain together or else reps will be deducted.
Pullups follow situps. A minimum of 3 are required to stay on the course but any less than 5 will be looked at critically and 16 will gain the maximum score. The over-grasp grip is used, the candidate is required to pull and hold the position until told to extend the arms; pull-ups are performed to the “bend” and “stretch” commands. The candidates chin must pass over the top of the bar to count and on the way down our body must be straight hanging down from the bar. Your legs must not cross. If the chin does not satisfactorily pass above the bar, or candidates cannot keep up with the commands, the candidate will be told to “drop off”.
The pool assessments include jumping off a high diving board (3m) in normal swimming kit and swimming a maximum of 4 lengths (approx 100m) of breast stroke followed by retrieving a brick from the bottom of the pool which is 3m deep. Train these skills. That brick retrival can be tricky. Learn to swim outdoors, in the cold, in clothes. For God sake have a life guard nearby. I think there are some outdoor swimming places like this one in the Royal docks in East London.
Other testing includes
The “Tarzan Assault Course” conducted up to 30 foot off the ground. Deal with your vertigo issues, or don’t apply!
The bottom field assault course which involves team games and other arduous physical activities.
An endurance course lasting 90 minutes and covering 2.5 miles undertaken on Woodbury Common
An over-night exercise which is intended to promote team building.
To train these, you’d better be a regular at your local Tough Mudder or Spartan Race. You need a t-shirt that says “I do love an obstacle race”. As I have said else where, if you don’t like getting wet, feeling cold, being woken up in the middle of the night, you really don’t want to apply for one of these programs, or the actual army for that matter. Familiarity with rope climbing and ab-sailing can probably be obtained at your local climbing centre. In the East End we have the Mile End Climbing wall
If you want to apply to be on SAS Who Dares Wins click here
If you are insane enough to want to do this, feel free to ask me for some in real life (if you are in the East End of London) or Online PT sessions.
There is a lot to be learned about how you, and the people around you breath. As a trainer and 1st aider, I try and observe carefully how people breath.
A normal breathing pattern consists of between 12-16 (some argue 12-20) breaths a minute aka your respiratory rate. From a first aid and general fitness perspective breathing patterns out of this range should be investigated.
Respiratory rate has been described as the neglected vital sign, for instance a respiratory rate higher than 27 breaths/minute is one of the most important predictors of cardiac arrest in hospital wards
Changes in respiratory rate seem to be much greater than changes in heart rate or systolic blood pressure meaning that respiratory rate is likely to be a better means of discriminating between stable patients and patients at risk.
21% of ward patients with a respiratory rate of 25–29 breaths/minute assessed by a critical care outreach service, died in hospital. However, its not just the rate of breathing that indicates your current state. How you breath can be critical.
So, can you describe how you are breathing?
Here are some useful descriptive words that will help you categorise and explain to others what you see.
breathless: breathing very fast and hard, for example after exercising
winded unable to breathe because you have been running or have been hit in the stomach.
Obviously you need to put these observations in context. If someone has just sprinted 400m, they will be breathing heavily and be out of breath. But you can see why. If someone has been sitting down for the last hour and they have a breathing rate of 27, you really ought to be getting some help. Apart from breath counting, it’ as well to notice how people are holding themselves, or their posture.
People with breathing issues often adopt a tripod position which is a “Physical stance often assumed by people experiencing respiratory distress or who are simply out of breath. In this position, a person sits or stands leaning forward and supports the upper body with hands on knees or other surface”(source)
its actually quite a tricky muscle to stretch. Interestingly it inserts into the shoulder and then skips over to the forearm. Speaking with my therapist hat on, I’d say 85 % of shoulder problems have a “poor relationship” with the bicep. Getting some sort of stretch in, is therefore, good.
Stretch No 1
The “just straighten your arm” stretch. Do what it says on the tin. It’s better than nothing
Stretch 2 is more fun. Sit down with your arms behind you and start sliding your bum forward. You’ll either feel the stretch in the elbow, the shoulder or in the belly of the muscle. Over the weeks, focus on getting your hips further forward to increase the stretch. Build to 2-3 minutes
Number 3 is a disgusting stretch, so make sure you have built some stretch capacity by pushing Stretch 2 along for a few weeks. This hanging stretch is stolen from gymnastics and is called the German Hang. Find a low bar, hang off it. Pull your knees through your arms then keep on turning. Lower your legs to the floor and hang in your shoulders. Do start this with a low bar, as you may need to drop straight off even as you get into something resembling the position. Its very intense!
It also helps you understand the meaning of the word “intense”
If you can run 1 mile in sub 8 minutes: run 1 mile (1.6k) to equal or beat your last 1 mile time. Rest that amount of time, then run 1 mile (1.6k) . Attempt to keep the same pace ( or faster). ( this amounts to 2 miles (3.2k) in total.
If it takes you longer than 8 minutes to run a mile, run 1K as fast as you can; rest the amount of time it took you to do the 1st 1k. Then run 1 k again. ( 2k in total, not miles)
If your 1 mile (1.6k) time is between 8 and 9 minutes you can choose which task you feel will benefit you more. But we are looking at pace and speed if possible.
(new runners feel free to pick 400, 600, 800m as your distance)
Whilst I talk about the various therapies and stretches for Plantar Fasciitis here, its worth tuning into the “length of stretch” debate.
If you look at Porter D, Barrill E, Oneacre K, May BD. The effects of duration and frequency of Achilles tendon stretching on dorsiflexion and outcome in painful heel syndrome: a randomized, blinded, control study. Foot Ankle Int 2002;23(7):619-624.
You’ll find two protocols coming neck and neck:
3 minute of stretching 3 x a day, or five sets, 20 seconds each, two times daily.
Either way, the take home message that a quick reluctant 10 second stretch when you can be bothered, isn’t enough. The study also determined that both sustained and intermittent Achilles tendon stretching exercises increase Achilles tendon flexibility. This increase in flexibility correlated with a decrease in pain!