Tackling the Hills

How do you run hills – go hard to reduce the time you are slowed down by the hill, keep your pace the same all the time, or keep it relaxed going up and then surge after? That’s the question that researchers had with this study: What is the best way to tackle the hills?

Before we get into the details, we have to cover some geeky stuff. “Ventilatory Threshold” (VT) is when you start breathing heavily (when exercising! ;)) due to lactic acid accumulation. Lactate Threshold is the point at which lactic acid produced in the muscle is not cleared as fast as it is being produced. This lactic acid is then broken into lactate and acid (hydrogen ions). The lactate is recycled and used as an energy source, while the hydrogen ions are neutralized in the blood, with a by-product being CO2. The CO2 then needs to be expelled through ventilation. This is called Ventilatory Threshold (VT) and is characterized by a sudden heavy ventilation and an increase in CO2 being expelled in the breath.

The researchers took experienced runners (all with a PR of under 40 mins for a 10K) and had them do a 3 loop, undulating 10K course, all the while hooked up to a portable gas analyzer, heart monitor , accelerometer to measure stride length and frequency, and a Global Positioning System (GPS) receiver to provide continuous velocity and location data.

Here’s what they found:

· Runners ran 13.8% faster on the downhill’s and 23% slower on the uphill’s compared to the flat sections

· Stride frequency was remarkably similar across all sections

· Stride length was 20.5% shorter going uphill and 16.2% longer going downhill compared to the flat sections

· Going uphill, runners averaged just over 100% of their VT. In other words, they were limited by their cardiovascular system

· Going downhill, runners averaged just under 80% of their VT, however there was a large range here (between 64.5- 93.7 % of VT). In other words, some were not even close to being limited by their cardiovascular system

· This is a big key point: There was a “lag effect” when transitioning between gradients. For example, following an uphill, speed increased relative to the uphill speed, but there is a lag time before the runners got back to normal speed. In this case, an average of just under 80 seconds before they got up to normal level ground speed. Presumably this is due to runners being forced to recover from the high anaerobic cost of the uphill.

· There was also a lag effect on speed following downhill sections: Speed remained elevated following a downhill on subsequent level sections where this “lag effect” on speed persisted for almost 80 seconds. In other words, following a downhill section, speeds remained increased for a period on the flat section. In part, this may be due to momentum, but also to a gradual return to increased oxygen consumption.

Why all this minutia is important:

· Since it took an average of almost 80 seconds to recover from an uphill run, the researchers calculated that it would be better to take the uphill’s slower to avoid the needed recovery from the hill. In other words, if the time you lose going up the hill slowly is made up by a quicker recovery, your overall time will be faster.

· This was confirmed because the runners in the study who had large variations in pace with respect to the uphill or downhill had the fastest overall times. This is because they slowed going uphill, but took advantage of the flats and the downhill’s.

· Taking advantage of the downhill’s also takes advantage of the lag time when you hit the flat section at the bottom. If your speed is increased for nearly 80 seconds without approaching your VT, that would be an advantage.

· The idea is to not vary your oxygen consumption much. For example – going hard uphill can use up to and over 100% of your VT, while taking it easy downhill can take as little as 64% of your VT. If you keep it consistent, it would mean going slower uphill – say 90% of your VT and then going harder downhill – say 85% of your VT. The researchers stated ” One possible suggestion for minimizing time then on hilly courses may be to balance the time cost of running slightly slower uphill’s, with the potential time saving if runners can return to a faster speed on the level in a shorter time frame. Similarly, runners should take full advantage of running faster on level sections following a downhill but limit increases to keep VO2 just below their ventilatory threshold. This was supported by our findings on the effect of hills on subsequent level sections where a lag effect on speed persisted for almost 80 seconds. This research has suggested that these level sections following hills represent the most likely source of potential improvements for runners wishing to minimize their overall time in distance races on hilly courses.”

OK, here’s the caveat…

Running downhill fast is hard on the knees! When running down a -9% grade at 3 m/s, it has been shown to increase normal and shear forces on the knees by 54% and 73% respectively, when compared to running on flat ground (full study found here). Therefore, it’s possible that some people may need to slow down on the downhill, simply as injury prevention to reduce the shock on the knees. This puts the limiting factor on downhill speed as a biomechanical limitation, rather than a physiological one.

One way to attenuate the risk of injury of downhill running is to….(are you ready for this?….this is great because it dovetails with the last newsletter)…strength training!!

Heart efficiency relates to brain aging

A new study in the August 2 2010 Journal of the American Heart Association shows what runners have known all along…our brains are bigger! OK, in all seriousness, this is an important study with long term implications. We know that as we age, the size of our brains decreases – just as muscles atrophy, so does the brain. More severe brain atrophy occurs in those with dementia, such as Alzheimer’s disease. By using MRI’s, this study found that decreased cardiac index (the amount of blood that pumps from the heart in relation to a person’s body size) was associated with reduced brain volume. In other words, reduced brain size was associated with the heart pumping less blood.

This was a large study – 1,504 participants in a decades-long study who did not have a history of cardiac disease, stroke, transient ischemic attack or dementia. The researchers noted, “We observed cardiac index is related to structural changes in the brain but not cognitive changes,” Also, “The structural changes may be early evidence that something is wrong.”

The exact cause between heart function and brain volume is still not well understood, the researchers said. “There are several theories for why reduced cardiac index might affect brain health. For instance, a lower volume of blood pumping from the heart might reduce blood flow to the brain, providing less oxygen and fewer nutrients needed for brain cells. It is too early to dole out health advice based on this one finding but it does suggest that heart and brain health go hand in hand.”

The crux of the study is this – while this is an observational study, (i.e. no cause and effect established yet) we know that exercise increases the cardiac index. If cardiac index is associated with reduced brain aging, it makes sense that exercise reduces brain aging. In fact we already know that.


Other related studies:

· This study looked at 1740 people aged 65 or over, all of whom began the study with good cognitive function. After six years, 158 people in the group had developed dementia (107 of the 158 had Alzheimer’s). But those who had exercised at least three times a week were on average 38% less likely to have developed dementia than those exercising less than three times a week.

· This 21 year study of more than 1,400 adults, those who exercised during middle age were 52% less likely to develop dementia and 62% less likely of developing Alzheimer’s than non-exercisers.

For those about to Cramp…

Training in the heat this summer has taken a toll on many runners. I hear many of you complaining that your pace has slowed down or you are just not training as much. Some, however, have suffered the much feared…muscle cramps – in a run, bike or pool. Is it the heat, or some other evil beast? I was a victim just this week when I had done a long run in the morning and then was out very far away from home on a 50 mile bike when I started cramping. First my calves, then my quads. Not fun!
Two studies have emerged recently that have shed some light on muscle cramp prevention as well as treatment.
If we look at the history and theory of muscle cramping, it’s traditionally thought that electrolyte imbalances were solely to blame.  However, this theory of why cramping occurs is being thrown into question. It appears multifactorial.  For example, if it’s a systemic depletion of electrolytes, why is it the muscles that are working harder are the ones that usually cramp?  Why isn’t it the entire body?
Secondly, several studies comparing cramp-prone athletes with non-cramp-prone peers have found that that hydration and electrolyte levels in the two groups are almost indistinguishable before and after the race. One such study is found here. This study concluded “EAMC (Exercise Associated Muscle Cramps) in Ironman triathletes is not associated with a greater percent body mass loss or clinically significant differences in serum electrolyte concentrations.”
That brings us to the first study, not yet published but reported on here, which deals with overtraining and cramping.  This study of triathletes found that those who developed cramps had started at faster paces relative to their previous best times compared with non-crampers. And in a further study (again, not yet published), the same researchers found that crampers tend to have trained more in the final week before the race. As a result, the had elevated blood levels of enzymes related to muscle damage before they start.

This means that if you haven’t rested enough before a race or if you start a race or a training session too hard, you are setting yourself up for muscle cramps. It’s likely a result of several different factors coming together, including genetic predisposition, but at least we can now try to change some factors to prevent the cramps in the first place.


The next study (published here) is also to do with cramping, but instead of prevention, it’s to do with treatment.  Here, they dehydrated subjects, then electrically induced muscle cramps.  One group received nothing to treat it, the second group received deionized water and the last group….around 70ml of pickle juice (about 2.5 oz).
The results were thought provoking:  the pickle juice group’s cramps stopped about 45% faster than the no treatment group and 37% faster than the deionized water group.  On average – the pickle juice took around 85 seconds to stop the cramps.  Why is it thought provoking?  Because we know pickle juice electrolytes would take around 30 minutes to go through the stomach, absorbed through the intestines and get to the muscles.  So, if it takes 30 mins for the electrolytes in the pickle juice to actually get to the muscles, yet it stopped the cramping in 85 seconds, it’s obviously not the actual electrolytes. Everyone assumed that the electrolytes were the cause of muscle cramps…maybe not!

The researchers suspect that that mechanism is simply – exhaustion. Biochemical fatigue, or direct fatigue of the muscle. When a muscle is very tired, we know that certain mechanisms within muscles cause them to start misfiring. Small nerves that should keep the muscle from overcontracting malfunction, and the muscle bunches when it should relax. So, they think that the pickle juice somehow acts on neural reflexes – receptors in the mouth and throat disrupt the misfiring neurons. This fits with an alternate theory that cramps have nothing to do with dehydration or electrolyte loss, first proposed in the 1990s byMartin Schwellnus of the University of Cape Town:

Early observations have led to the belief that cramps in athletes are caused by shortages of electrolytes (sodium, chloride, and magnesium), dehydration, or heat. Despite a lack of scientific support for these theories the term “heat cramps,” which was first used in 1935, is still in use today. However, there is increasing evidence that EAMC is caused by muscle fatigue which results in a disturbance in the normal control of the nerves that cause muscle contraction. A number of researchers who have reviewed the medical literature now conclude that this “altered neuromuscular control” mechanism is probably responsible for the majority of EAMC in athletes 21-23.  As with other forms of cramping, a small proportion of EAMC may also be as a result of underlying medical disease or drugs 21;23.


Does this all say to stop with the electrolyte replacement fluids when running? No, of course not. There are still things like hyponatremia that we have to worry about. All this is saying is that exercise induced muscle cramping, while thought to be due to electrolyte deficiency, really has more to do with fatigue. If you’re prone to muscle cramps, watch for overtraining, start your races conservatively and, if you must, bring some pickle juice with you!

10 Changes that Shook the Running World (past decade)

Steve Boyd is a three-time Canadian champion on the road, X-C and track with personal bests of 13:46 for 5k, 28:41 for 10k, 1:03:36 for Half Marathon and 2:17:28 for the marathon, all after the age of 30. His blog can be found here.

I read his blog occasionally but unfortunately I had missed this POST which I thought was interesting and thought was interesting. In particular, his #5 change which was…”Active Release Technique”. As I was reading his post, it was my intention to post it even before I read his endorsement of ART. That plug for ART just made it better! 😉

SBoyd_B+W

Strength Training for Endurance Athletes

Ask 10 different endurance athletes if strength training is important and if they incorporate it into their overall training and you’re likely to get many different responses. Answers will vary from “very important” and others will tell you that strength training has no role in endurance sports, or “I have no time”. Let’s look at the research pertaining to strength training and running…

One concept that we have to understand before we delve into the research is that of “running economy”, or RE. RE is basically how fuel efficient you are. It’s the same as a car – if your tires aren’t properly inflated, if your engine needs serviced, if you’re driving too fast or if you’re driving a heavy vehicle, you will use more fuel to get where you’re going. In running, we can look at the amount of oxygen you consume per minute and see how that varies when you run at various speeds. The amount of oxygen you need to take in at a given speed is your running economy. In other words, if you need to consume X liters of oxygen per minute to run at 8 minutes per mile and then you do a different type of training for 4 weeks and retest your RE and now you need less liters of oxygen per minute to run at 8 min/mile, it would mean you are now running more efficiently and should be able to run further at that pace, or faster without working harder.

A study in 2008 took a group of runners and had them perform half-squats: 4 sets X 4 reps 3X/week X 8 weeks in addition to their normal endurance training . They found that the RE improved 5% and time to exhaustion at max aerobic speed improved 21%.(1)

There are many more studies like that one, but I’m not about to list every one of them. The point is: strength training improves running economy. The next question is usually “how many reps do I do?” A 2009 study took runners and split them into two groups: one group did lighter weight and high reps (3 sets of 12 reps) and the other group did heavy weight and lower reps (3 sets of 6 reps). Both groups continued with the same running schedule and all the strength exercises were the same (leg press, parallel squat, leg extensions, leg flexions and calf raises). The only difference was the amount of resistance and the number of reps. In the end, “there was a significant improvement in RE in the high weight/low rep group (6.2% improvement), but not the low weight/high rep group (only 1.9% improvement). (2)

No time to add strength training you say? Let’s look at a study that replaced 32% of the training time with explosive strength training. Over a 9 week period, the runners had their RE improve by 5% and their 5K time improve by an average of 3.8% – that’s over a minute if you’re a 9 minute miler!(3)

In the interest of brevity, we’ll end this article here, however, there’s much more benefits of strength training including injury prevention and hormonal responses. Should you have any questions regarding this article, please email us at contact@activespineandsport.

1. Storen et al., Med Sci Sports Exerc. 2008 Jun;40(6):1087-92
2. Guglielmo et al., Int J Sports Med. 2009 Jan;30(1):27-32
3. Paavolainen1 et al., J Appl Physiol 86: 1527-1533, 1999

STOP overuse sports injuries in kids

The newly launched STOP sports injuries program has taken aim at preventing overuse injuries in sports. Overuse injuries are injuries that occur when a tissue (muscle, tendon, ligament, bone) is used too frequently and intensely that it becomes fibrotic and possibly tears (or in the case of bone, results in a stress fracture). The group sees two disturbing trends: a rapid rise in the number of youth sports injuries and a drop in the age of young athletes with overuse injuries. According to the American Academy of Orthopaedic Surgeons, every year more than 3.5 million children age 14 and younger are treated for sports injuries. 50% of these are overuse injuries.

Some of the founding members of the program include former Olympic champions Christie Rampone, Eric Heiden and Bonnie Blair; professional golfer Jack Nicklaus; NFL Hall of Fame quarterback Bart Starr; MLB baseball player John Smoltz; NFL Hall of Fame defensive end Howie Long; and Heisman Trophy winner Sam Bradford.

Another major spokesman for the group is renowned orthopedic surgeon to the sports professionals, Dr. James Andrews. One of the major problems he sees is that these days, kids are encouraged, if not forced to specialize in one sport, and then the sport tends to be year round. Dr. Andrews reports “Sports used to be seasonal. If you played youth baseball, you used to have the winter off. Now, people think playing all year is supposed to make you better, but more isn’t always better,” John Smoltz, who’s now a TV sports broadcaster, agreed. “Growing up, I played all sports and loved every moment of it. I didn’t feel like I had to compete in such a magnified way to get recruited or looked at. If you asked every other major leaguer, and other professional athletes, very few would say that they played their sport year-round,” Smoltz said. “These kids need time to recover and play other sports,” he added.

We certainly see this in our practice. Our main tool of treatment is Active Release Technique, a technique specifically designed to treat overuse injuries in soft tissues. We certainly see quite a number of kids in our practices and we always try to promote cross training and sometimes, time off from activities. Heck, if you watch the March 23rd post made on this website, you will hear Dr. Kevin talk about the importance of cross training for marathoners when he spoke at the Suntrust National marathon.

Parents and coaches need to be aware of how these kids are feeling and there has to be an open line of communication between the child, parent, coach and health care provider.

Watch an interview on FOX News below with John Smoltz, Sam Bradford and Dr. Andrews:

Their website is found here

Post run leg workout and Athena routine

I’ve always been a fan of coach Jay Johnson’s work – he stresses that runners do a good bit of general strength work along with their running. Here’s a good example of a post run leg workout, followed by his “Athena routine”
Keep in mind you probably don’t want to do this type of routine prior to your run. There is a great deal of core work involved. If you do the workout pre-run, you will fatigue your core muscles (glutes, torso hip flexors etc) which are so important for stabilizing everything when you run. If they’re fatigued, you get poor stabilization, and potential injury. Make sure this is done after the workout.

SV Leg Circuit, then Athena (uncut) from CoachJayJohnson on Vimeo.

Is running bad for your knees?

It’s strange how many people believe and then perpetuate the myth that running causes “knee problems” later in life.  If you’re a runner, and someone tries to tell you that you’re doing more harm than good, feel free to refer them to these quick points of research (which is just scratching the surface of available literature):

1) 1986 – This study compared the knees of runners vs. non-runners.   The runners ran an average of 28 miles/week for a 12 year period.  Pain in the hips, knees and ankles was not more prevalent in runners vs. non-runners.  Also, x-ray findings and did not show increased arthritis in runners vs. non-runners.  Journal of the American Medical Association. 1986;255(9):1152-1154

2) 2009 – This study reviewed all previous studies done up until January 2009.  They found that:

  • “The best evidence suggests that exercise, at least at moderate levels, does not accelerate development of knee osteoarthritis. Running seems to be particularly safe.
  • “marathon running does not seem to induce changes in joints or increase the risk of osteoarthritis in most studies.”

They also found that in runners…

  • “There is evidence for reduction in lower-extremity disability and all-cause disability in self-selected runners compared with controls.”
  • “There is some evidence for prolongation of lifespan in self-selected runners.” Canadian Family Physician 2009;55:871-878.

3) 2006 – This was another review study, done solely on long-distance running.  They found it does not increase the risk of osteoarthritis of the knees and hips for healthy people and “that this activity might even have a protective effect”.  They went on to tout the other benefits of running by citing other research findings: “Running has been shown to decrease the risk of cardiovascular disease, diabetes mellitus, and depression. This kind of physical activity has also been shown to help with weight control, to improve bone density, and to decrease mortality.Journal of the American Osteopathic Association 2006;106:342-345