mercredi 18 juin 2014

64. Results of the long-term survey conducted among midfoot runners (part 1)

I released my ebook "Courir Léger - Light Feet Running" its first version over a year ago.

To try to better understand the consequences of the implementation of the midfoot stride (especially as I have described and explained it in the book), I sent a questionnaire of 19 questions to 150 readers of my book on a random basis. Within 10 days, 71 readers had kindly answered (a very satisfactory rate of 48%) and I sincerely thank them.

Given the results of this sample of 71 players and in order to present the results in a meaningful way, I decided to separate the answers into two groups: on the one side, runners who have been practicing the midfoot strike for more than 6 months (61% of the respondents) and, on the other side, those who have been practicing it for less than 6 months (39% of the respondents).

Here is the analysis of the first group of runners, those who practice the midfoot stride for more than six months. For the sake of clarity, I dissociate facts from my comments (written in italics).

1) Sex

The sample of 43 runners were composed of:
- 95.3%: 41 men
- 4.7%: 2 women

2) Age / Frequency / Type of practice

Their age range was:
- 36-45 years = 50%
- 25-35 years = 18.2%
- 46-55 years = 15.9%
+ 55 years = 15.9%

These riders were practicing:
- 3 times per week (18 citations)
- 4 times per week (16 citations)
- 1 or 2 times a week (8 quotes)
- 5 times a week (5 quotes)

Their practice was:
- Road race (22 citations)
- Triathlon (16 citations)
- Trail (13 citations)
- Ultra-Trail (4 quotes)
- Ultra-marathon (2 quotes)

The midfoot experience of these runners is as follows:
- 40.9% for more than 6 months and less than 1 year
- 38.6% for 1 year and less than 2 years
- 20.5% for more than 2 years.

Comment:

The sample thus relates quite diverse practices in slices typical age of amateur rider with a rather regular, almost exclusively by male runners.
 
3) The consequences of the midfoot stride on the chronometric performance

A little less than a quarter of the riders said they have not improved their chronometric performance (24.4%). Only one rider answered that he had regressed in terms of speed.

36.6% of riders said they experienced a slight improvement and the same percentage said they experienced a real chronometric improvement.
 
3/4 of the riders improved their speed a result of the implementation of the stride midfoot.

Comment: I will discuss in a future article link (or not) between morphotype and improving performance.

4) The implementation of the stride and midfoot injuries

We read so often that the change in stride cause injurie, it was interesting to ask these riders if they got injured by implementing the midfoot stride.

60.5% of runners respond negatively: they did not get injured when they implemented the midfoot strike. 39.5% of riders said they got injured.
 
Comment: it should be noted that in general, the percentage of runners who get injured is around 60% to 33% depending on the studies. Implementating the midfoot stride therefore does not hurt the runner more than the mere practice of running (or even less). I will refine this comment in an upcoming article analyzing these injuries.

The most quoted injuries are the following:
- Foot: 20 (and largely by runners running barefoot or in VFF)
- Ankle:
- Knee: 2
- Hip: 1
- Lower back:
- Hamstring:

Now regarding the effect of the midfoot stride on correcting injuriesonly 6 runners say their injuries were not resolved. Injuries resolved were:
- Knee: 9 

- End of orthopedics insoles: 9 
- Lower back : 6 
- Length: 5 
- Ankle: 4
- Hip: 3

Concerning the effect of the midfoot stride on the calves (there were multiple answers possible):
- 24 runners say they have not really experienced this kind of problem
- 19 runners had that king of issue at the beginning but it quickly disappeared
- 13 runners say they got injured in this part of the body and/or have repetitive issues in this part of the body. Many of them emphasize the importance of the transition from heel striking to midfoot stride.

5) The effects on the runner's body:

Almost all runners (90.7%) said they felt effects on their body as a result of the implementation of the stride midfoot.

These effects are (in order from most to least cited):
- Calves reinforcement (24)
- Feet reinforcement (21)
- Glutes reinforcement (16)
- Change in the tear of their shoes (16)
- Abdominal reinforcement (10)
- Quadriceps reinforcement (1 quote)

Only 4 of the 43 runners replied that they have not perceived any effect on their body (and mostly, these are the riders who say they are using shoes weighing over 250gr).

6) the effect on the pleasure of running:

42 of 43 riders said they improved their feeling of pleasure by running with midfoot stride. Only one rider replied no.

7) following the advice of my ebook:

62.8% say they apply the largest part of the recommendations in the book.
34.9% say they apply some of the tips of the book.
2.3% say they do not follow the tips of the book.

8) alternating with another stride

Almost 2/3 of the runners say they do not practice a stride other than midfoot stride (67.4%). 18.6% say they switch from one stride to another (these responses are particularly from trail runners).

Comment: I find this interesting because it shows that more than two thirds of the riders have adopted once and for all this and only this midfoot stride. This shows that they have found that this stride better suited them than their previous stride.

9) mastering the midfoot stride:
 
Only 6 riders (14% of the sample) say they do not think they master the midfoot stride. Please remember that half of the sample is composed of riders who have practiced stride midfoot for 6 months and less than 1 year.

Comment: This figure suggests that this skill does not take so long to master (we can refine this analysis in the second part of the study will be devoted to practicing runners stride midfoot for less than 6 months).

68.2% of runners did not film themselves to observe their stride ; 31.8% of runners are filmed to observe their stride.

10) the type of shoe used

Here is the order of shoes by riders (from the most used to the least used):
- Lightweight shoes (between 150g and 250g): 29 
- Minimalist shoes (less than 150g): 10
- Traditional footwear (250gr +): 10 
- VFF or equivalent: 9
- Barefoot:

Runners run therefore primarily with light shoes. Many runners use several models of shoes falling in different categories.

It seems that the runners who use traditional shoes are those who encounter the least benefits from the midfoot stride.

11) drop of their shoes

Here is the drop  of the respondents' shoes
- 4 to 6mm: 16
- 0 to 4mm: 15
- 0: 12
- Between 6 and 10mm: 11
- + 10mm: 1

12) the reasons for a midfoot stride

The main reasons to switch to a midfoot stride are:
- To optimize its stride (38 answers)
- To heal an injury (21 answers)
- Suggestion by the media (12 answers)
- Friend's advice (3 answers)
- Coach's advice (3 answers)
- Health professional's advice (1 answer)

Comment: apparently, professional (coach or health professionals) are not very aware of the benefits of the midfoot stride.
Conclusion:

This study shows that no one should be dogmatic regarding the running stride.

The old theory that runners will hurt themselves if they change their running stride failed to be proven by this survey. Indeed, the vast majority of the survey respondents did not get injured by changing their stride towards a midfoot stride.

The theory that everyone has an instinctive "natural" stride also failed to be proven : almost all of the runners replied that they have more fun in running than before and the vast majority has seen its speed improve. They add that they are practicing only the stride midfoot (and no other stride).

On the other hand, the idea that there is a perfect stride that prevent runners from getting hurt is not proven by this survey; a runner may well get hurt running midfoot with an increased risk of feet injury for runners who practice barefoot or use VFF. We can therefore deduct that wearing shoe has undeniable advantages in preventing certain injuries.

The sample of runners practicing the midfoot stride with maximalist shoes was low in the study. Based on their responses, these runners do not seem to take full advantage of the midfoot stride (particularly they feel less positive effect on their body but the sample was very small).

It is fairly interesting to notice that the results of this survey are very close to those recently conducted by Dr. Jay Dicharry titled "Barefoot Running: Evidence from the Field", published April 24, 2014 in the Journal of Sport and Health Science (link: HERE.) for example, regarding the percentage of injuries and the percentage improvement in performance. 

The second part of the survey will deal with the runners who have been practicing the wake midfoot for less than six months.

(To be continued ...)