It is very clear that running on down slope is faster than running on flat land. It is because a tractive power generated by gravity is pulling you down in addtion to a leg power. Every one knows that it is very important being bending forward for sprint. But all athletes rise up their bodies gradually like standing bolts upright as they leave from start line. Why can't they keep their bodies forward tilting from start to goal? I will clarify the cause and introduce a way of fore posture in sprint through out race which I found accidentally.
Let's brush-up dynamics how powers act on your body in sprint based on the figure below.
O is the fulcrum which the ground touches a tiptoe with.
OA = OB = Height
C = Center of gravity
A1 and B1 are rotatory forces to depend on C.
A2 and B2 are repelling powers from the ground hanging in C.
A3 and B3 are tractive powers to depend on C.
W is weight.
Angles of inclination from perpendicular for OA and OB are 20 and 40 degrees each.
D and E are ranges of wind pressure hanging in the OA and OB each.
You can tell the following facts from above figure.
1. The more angle it takes, the more tractive power is generated. (A3 < B3)
2. The more angle it takes, the less repulsion from the ground you get. ( A2 > B2)
3. The more angle it takes, the less range of the wind pressure is affected. (D > E)
CONVENTIONAL RUN: Why do they rise up their body after standing or crouching starts in sprint ? It is because they take dash start at beginning and keep running with full speed to the goal. Their starting speed is not fast but it will gain more speed gradually by the repelling and the tractive powers. However they will not be able to keep the same bending angle because the speed will go over the limit of running power around 40 meters and fall down easily. That's why they need to reduce the tractive power gradually by rising up their body for decreasing angle. In other words they can not but reduce the bending angle and tractive power inverse proportion to speed rising. It is impossible to keep their primary bending angle through out a race by kicking ground at the full speed.
PROPOSAL RUN: Then how can you run with fore posture from the beginning to the end ? It will be solved the problem by taking standing start. Take on your mark with normal standing start posture and your upper body being bent at "SET". Kick the ground slightly harder (70~80% of your start dash power) by a rear foot at "GO" and let your body fall down forward. Then your body becomes fore posture spontaneously and your rear foot step forward unknowingly to avoid a fall down to front. Let your body go freely then it will take little more angle. Then again your another rear foot also step forward automatically to avoid a fall down. Your body increases an angle of inclination while such a movements are repeated and your running speed becomes faster beyond comparison with the conventional run. The rear leg also leap up more higher than traditional one and it is the evidence that the speed of proposal run greatly exceeds the one of conventional run. You need to stop increasing of the slant by bringing your face up a little when the speed approaches the limit of your running power. You should keep that angle and run with the same posture until goal. It is the most important point that you must transfer your body to fore posture while your enough running power can afford. No dash, no lash and no kick hard ground consciously on your run way!! Let's use the tractive power generated by gravity!!
COMPARISON BETWEEN CONVENTIONAL AND PROPOSAL RUNS IN SPRINT: You can put your center of gravity on a perpendicular line of start line for standing start. It has an advantage of about 1/4 foot ahead of crouching position at start line.
You have to lift your center of gravity against gravity from lower position to higher one for crouching start. In comparison with it you can easily bring it down according to gravity from upper position to lower one. The difference of spending energy between both starts is considerably big.
You feel considerable repelling power all the way for the conventional runs. That means you are kicking ground considably hard. On the contrary you slightly feel it due to gradual reduce of repelling power for the proposal run. It means that you only need to kick ground with less power.
To put it concretely you run by leg power for the conventional run but you run by the tractive power occurred by angle of inclination, leg power plus less wind pressure
Of course I am not saying that you don't need athletic training for leg power and muscular strength. you need them for lengthening strides and making the quick movements of legs and arms.
On this proposal run you don't feel that you are kicking the ground due to reduction of repulsion from the ground but you feel that you are pulled from the front.
FEELING OF PROPOSAL RUN: It's obvious that running on a downhill is faster than running on a flat land. This proposal run is like a running on the downhill slope. You can run with kicking back the ground slightly harder at first and after that the tractive power let your body go ahead without kicking the ground consciously. This is what the tractive power mentioned in the figure above is affecting to your body. Your running speed increases and you start to put on the brake when the speed approaches the limit of your legs power. At this point you are in a state of delicate balance. On proposal run you are in the same state. You might fall down if you get an even slight power from outside. Therefore this proposal run is not suitable for the competitions that may touch other. In other words this run is for competitions of separate courses like 100, 200 and 400 meters.
SUMMARY:
1. Put your center of your gravity on a perpendicular of start line at the "SET".
2. No starting dash. Kick slightly harder (70~80% of start dash) the ground by rear leg and let your body fall down forward.
3. No kick the ground consciously on your run way. Let your legs and arms go by themselves.
4. Control your speed by bringing your face up and down. Face up is for restrain the speed and face down is for accelerate the one.
5. Strengthen muscle of your thighs to avoid fall down. Because an excessively heavy burden depends on them due to quickly movements of legs back and forth.
6. Search the best power for kicking ground at the "GO" and the best degree of leaning to bring you to the top speed quickly.
CONCLUSION: This proposal run was experienced by my self. I did not carry out physical exercise routinely and did not know much about athletics. But I happened to run for 100 meters in its 50 in athletic meeting of our small town and I found accidentally this proposal run. My time of the semifinal and the final runs were 14 and 13.4 second each. I did not expect a such good result of the final run and it made me surprise. And I had been thinking for long time why I could shorten 0.6 second which was almost equal to 6 meters. I had kept researching the reason and I arrived the theory of this proposal run.
I'm pretty sure you may shorten your record for 100 meters by 0.5 seconds and for 200 meters by nearly 1 second if you adopt this proposal run. According to the international rule standing starts are not permitted but it would be changed if someone try this proposal run unofficially and prove it is much superior than other runs. How you can run fast is the most important, and it is meaningless to limit a form of starts to crouching.
Masaaki Shirakawa
2-20-8 Ginowan
Okinawa Japan