Tape it up?

Watching all the fabulous sport this summer, it was impressive to see how many athletes were decorated with brightly coloured strips of tape. The use of kinesio tape has become widespread over recent years, but it first appeared way back in the 1970′s. It is claimed that the use of this tape can help reduce swelling and pain, stabilise joints and support muscles.  The tape is available in different thicknesses (which are different colours), and is applied in a specific way to the problem area.  It stretches with the body, so movement isn’t overly restricted.  The theory is that the tape lifts the skin and promotes the flow of lymphatic fluid under the skin. You can now buy pre-cut sections of the tape to allow you to try this technique out yourself, rather than having to go to a physiotherapist and pay to have it applied.

I tried it myself last summer as an alternative to a bulky back support when I was competing in an adventure race. It helped give me confidence that my back would be OK during the race, as I was aware the strapping was giving me support.  However, it didn’t feel like a miracle cure for my muscle strain; following the race, I was still stiff and sore.

Sports Medicine published a meta-analysis of ten studies investigating the use of Kinesio tape earlier last year.  They found only limited benefits to using the taping technique, including improving muscle strength and range of motion for people with certain injuries.  No strong evidence has yet been generated that supports the use of this tape above any other taping technique.

A study was published in 2011 that examined the effect of Kinesio tape on patellofemoral pain syndrome (sometimes known as runner’s knee). 22 women with patellofemerol pain syndrom (PFPS) were randomised into two groups; one that received kinesiotaping and one that received placebo taping. Immediately following the taping procedure, the participants were assessed in terms of muscle strength, propioception (awareness of joint position), balance and pain. No significant differences were found between the two groups.

In absence of any strong scientific rationale to support the choice of Kinesio tape, it could be argued that other factors have led to its widespread use.  The bright colours and distinctive patterns of the tape make it look cool compared to the boring skin-coloured varieties of tape.  Kinesio tape is a marketing triumph; it has developed a really strong brand image in recent years.  As long as professional athletes such as Novak Djokovic continue to embrace this technique, it is likely that its use will continue to increase in the general population as well. In spite of what the evidence says…

A pain in the side…

It’s a familiar and unpleasant feeling.  A nagging, sharp ache in my side appears out of nowhere and then hangs around for the rest of my run.  Stitches really are a complete pain! But what causes them and, more importantly, how can I get rid of them?

In 2012, a review article on gastrointestinal symptoms during exercise was published in Alimentary Pharmacology and Therapeutics. It included a section discussing stitches or, as they called them, ‘exercise-induced transient abdominal pain’ (ETAP). They stated the incidence of stitches at a running race was 18% of competitors.  Clearly, I am not alone in suffering from this problem!

ETAP is most commonly observed in sports that include ‘repetitive torso movements, bouncing or longitudinal twisting’, so it is understandable why runners suffer frequently from this problem. There is no conclusive cause of stitches identified to date in the scientific literature. One suggestion is that stretching of ligaments around the stomach area causes the problem. This would be aggravated by having a full stomach whilst exercising. An alternative theory is that it is a type of peritonitis; inflammation of the thin layer of tissue that lines the abdomen. It is proposed that a reduction of the fluid levels within this tissue layer causes irritation and friction, resulting in inflammation.

A study was performed by Plunkett and Hopkins in 1999, investigating side-stitches in runners. They found that movements that reduced the tension on abdominal ligaments rapidly relieved the pain of stitches. The movements they suggested were taking shallow breaths through pursed lips, bending forward whilst contracting the stomach, and finally, tightening a wide belt around the waist.  I’ve not tried the belt remedy, but the other two provide some measure of relief for me. They at least enable me to carry on running for a bit longer.

Other tips discussed in these two articles included not eating large amounts less than 2 to 3 hours before exercise, sipping drinks frequently rather than drinking large volumes in one go and avoiding hypertonic fluids before and during running.  Hypertonic fluids, such as fruit juice, are more concentrated than normal body fluids and slow the rate at which the stomach empties. Most of this advice seems to be geared towards reducing tension on the abdominal ligaments.

I can’t spot any triggers mentioned in these reports that correlate to my stitches. Mine seem to occur more frequently when I am running at a faster pace than usual for a sustained period of time.  I always thought that mine were tied to my fitness levels or, perhaps, operating at my aerobic threshold, where lactic acid starts to build up. Maybe it is linked to drinking too much, too often during my sessions and I need to take smaller sips instead.

What do you find triggers your stitches?  Do you have any tried and tested remedies? It would be interesting to see if the science done in a lab agrees with what we find when we run out on the streets and trails.

Running to a beat

My favourite running gadget has to be my heart rate monitor.  Not only is it bright pink, it has also made a huge difference to the way I train. Previously, I used to train based on a perceived rate of exertion which didn’t really suit my inner geek’s desire to see numbers and made it difficult to quantify my progress. My heart rate monitor on the other hand allows me to see how hard I am working and, as a bonus, it also calculates how many calories I have burned during my run. There’s a great video on how heart rate monitors work here.

I use my HRM in a fairly informal way; I know roughly what zone I want my heart rate to be in for easy runs, long runs and tougher tempo runs.  I haven’t yet determined my maximum heart rate to allow me to calculate my training zones more precisely.  This was a fun job (involving a killer workout) that I had set aside for the New Year, but an article I have just read made me think twice.

Lambert, Mbambo and Gibson reported some of the issues around the use of heart rate monitors in the Journal of Sports Sciences.   Although the monitors themselves are accurate in terms of the measurements they display, the interpretation of the data is not always straightforward.  I hadn’t fully appreciated that the day to day variation of our heart rate whilst running at the same pace can be up to 6 beats per minute (bpm).  There is also a significant effect on our heart rate due to what is known as ‘cardiac drift’.  This is the effect of dehydration during exercise on our heart rate, and can be summarised as that for each 1% loss in our body weight, our heart rate will increase by 7 bpm.  Even more of a surprise to me was the observation of a significant difference when heart rates during training runs and during races were compared, even though the pace that was run was the same!

The data reported in this study really made me think about the multiple factors that can affect our heart rates beyond the pace. Although the technology allowing us to monitor our heart rates is sophisticated, our ability to successfully interpret the output is limited, especially during runs.  Although I will definitely continue to use my heart rate monitor, I feel more relaxed about just using it as a crude way to assess how hard I am training.

The right fuel

Something I have often struggled with is getting the balance right for my nutrition when I’m training for an event.  I find it all too easy to justify to myself that I have earned a slap-up takeaway after a week of training. Making sure you get the right balance of nutrients to allow your body to recover and to strengthen is really important. As I approach my race this is something I’m starting to focus on again. Time to put the Christmas binging behind me!

After you’ve pushed your body hard during a workout, you need to replace the fluid that has been lost through sweat and also the glycogen that you have used from your muscle stores.  Glycogen is used as fuel during exercise, and is produced from the carbohydrates in your diet. If the body’s glycogen stores run low, you will feel tired easily when you are training. The storage of glycogen in the muscles is increased when protein and carbohydrate is consumed together, soon after exercise. The optimum ratio is around 3 to 4 parts carbohydrate to 1 part protein.

Perhaps surprisingly, low fat chocolate milk is a great recovery drink as it contains this ideal ratio of carbohydrate to protein. A study conducted by the University of Texas demonstrated that it performs well compared to purely carbohydrate based drinks. They conducted their research on trained cyclists who performed two high intensity workouts in the same day, taking either chocolate milk or a carbohydrate only supplement (of the same calorific value) after the first workout. Consuming chocolate milk post-exercise resulted in better recovery, as illustrated by physiological markers such as plasma insulin.   The chocolate milk group also demonstrated improved performance in the second workout.   Although this study was only on a small number of subjects, 5 male and 5 female, there has been subsequent studies performed that support these conclusions.

All of which is good news! Chocolate milk is not only good for me; it also satisfies my need for a reward after a workout.  With my long runs starting to stretch out over an hour now, the promise of that reward makes the final couple of miles a little easier to bear.

By haley8 (Playa Potrero Road Trip Uploaded by JohnnyMrNinja) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

 

Building the intensity

I’m trying to introduce more variety in my weekly runs at the moment.  Whilst running at a constant pace has helped me build a good base, I am now keen to increase my speed. It’s also a bit boring to run the same workout every day. Another unexpected benefit could be to my health. I recently read about a study demonstrating the benefits of interval training on both physical performance and biological markers. It was a good motivator to keep pushing myself hard on some of my runs!

Gunnarson and Bangsbo looked at the effect of a specific interval training programme on health profile, performance, muscle adaptation and maximum oxygen uptake compared against a control group, over a period of seven weeks. The subjects used for the study were moderately trained runners, whose bodies had already adapted to running at a constant pace. The interval training programme consisted of running at low intensity for 30 seconds, moderate intensity for 20 seconds then high intensity for 10 seconds for a period of 5 minutes, followed by a 2 minute recovery.  Three to four repetitions of the 5 minute ‘10-20-30’ intervals were performed.  The entire workout, including warm-up, was approximately 30 minutes in duration. The interval training group had about half the total run duration compared to the control group, who maintained a steady pace during their runs.

One drawback of this study is that only a small number of subjects were used: 10 in the interval training group and 8 in the control group.  However, both groups were evenly matched in terms of performance and physical characteristics.

It was observed that the interval training group increased their maximum oxygen uptake by 4%, ran 1500 m 6% faster and 5 km 4% faster than at the start of the study. They also reduced their blood pressure by 5 mmHg and their cholesterol levels also dropped. None of these changes were observed in the control group.

People new to running see significant improvements in their maximum oxygen uptake and biological markers from running at a constant, moderate pace.  As they become more experienced though, their performance and physical changes plateau. This study suggests that exercising at a greater intensity is a way of continuing to improve physical performance in more experienced runners.

Training Days

With a little over two months to go until the Bath Half, it is time to get serious about my training. Over the past month I’ve missed a few weeks running due to a nasty sinus infection and now I’ve got some serious catching up to do to get back on track. There’s lots of advice out there from experienced runners and one of the most quoted ‘rules’ is that you should never increase your mileage by more than 10% from one week to the next. I was curious to see if there was any evidence to support this in recent scientific literature and following a quick search, I came across a relevant paper in the International Journal of Sports Physical Therapy.

A systematic review of 63 articles was performed by Nielson et al to study if there was a correlation between training errors and the risk of injuries from running. The key factors examined were the volume of training (in terms of mileage per week) and the duration of training (in terms of time spent running per week). Some evidence was found to suggest a link between increasing mileage and increased occurrence of injuries.  It was, however, noted that there was no significant increase in injury occurrence for a 23.7% weekly rate of increase in training compared to a 10.5% rate. Intensity and frequency of running were also studied, but no conclusive trends were identified for these parameters. The evidence also suggested that novice runners were at a greater risk of injury than experienced runners, but that this could also be due to novice runners being more likely to report injuries than seasoned runners.  The article concluded that the complex interactions between volume, duration, frequency and intensity of training make it very challenging to make definitive links between training and risk of injury.

In my opinion, there is no solid evidence supporting the 10% rule summarised in the journal article. It seems that no single conclusive study has been performed to examine this widely held belief and the metadata is difficult to interpret across multiple studies.  Until further conclusive research is performed, applying common sense is, perhaps, the best approach. Personally, I feel comfortable increasing my mileage from 3 miles a week to 6 miles a week, even though that is an increase of 100%. However, the same increase from running a 20 mile week would be to run 40 miles. I think the key is to listen to your body and run according to how you feel.  I don’t think I’ll adhere to the 10% rule religiously as part of my training plan.

Barefoot Style

In recent weeks, I’ve been conducting a bit of an experiment on myself – I’ve been trying out a pair of transitional trainers.  My friends keep insisting that they are a miracle cure for nagging knee pain and tight hips.  But what is the science behind these claims, and what is behind the growing trend for minimal running shoes?

The principle is that humans evolved to run barefoot.  We all ran barefoot when we were young, usually landing towards the front of our feet.  However, as adults we wear trainers with large amounts of cushioning under the heel to protect us from the impact of running.  All that bulk around the foot has an impact on our gait when we run: approximately 75% of distance runners strike the ground with their heel rather than the forefoot.  The idea behind transitional and minimal trainers is to strip away some of that padding to bring the biomechanics closer to a barefoot running gait.

A recent study by Altman and Davis examined the biomechanics and injuries associated with barefoot running and traditional ‘shod’ running. The high load rates attained with heel striking were correlated with stress fractures, plantar fasciitis and knee pain, as well as issues with the large muscle around the front and sides of your shin. Running with a forefoot strike has been demonstrated to reduce the occurrence of these issues.

Running in a barefoot style results in a shorter stride length; this is also known to reduce the load rate on the leg and joints. It has also been reported that running barefoot minimises flexing and twisting at the knee and hip joints. There are indications that minimal trainers don’t provide the same level of benefit as running completely barefoot, as the feedback mechanism from the nerves on the sole of the foot is reduced. However, both minimal and barefoot running strengthen the muscles of the feet and ankles. Forefoot striking shifts the load on impact towards the back of the leg, and therefore calf strains and Achilles tendonitis are common, especially during the transitional period.  Transition to a barefoot style of running should be gradual to allow the body to adapt.

My own experience with transitioning has been mixed. My ankles, knees and calf muscles took a little while to adapt to my new gait, but have now strengthened sufficiently that they cause me no issues. Unfortunately, I develop pins and needles in my right foot a mile or two into every run. I plan to alternate between my transitional trainers and my traditional ones for the next couple of months. Hopefully, this will allow me to maintain the mileage I need to improve my fitness for the half marathon, whilst continuing to transition to a forefoot strike.