Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Filtering by Category: "Sprinting"

Day 340 - Running Speed

The mechanics involved in human running is substantially different than when walking. When human beings walk, the body rotates through various positions including balancing on one leg, while the weight shifts from one leg to both legs, to again on one leg. There is a cadence that rotates through these general positions.

Running, on the other hand, is more of a ballistic action with the body continually launching its weight from one leg to the other. The speed at which someone runs is directly linked to the stride frequency to stride length relationship. For example, when comparing novice to elite sprinters, studies have shown that elite sprinters achieve greater stride length and can increase it further up to about 45m from a static start of a race. Compare this to novice sprinters who peak their stride length around the 25m mark of a race from a static start.

When comparing novice to elite stride frequency, elite sprinters can achieve faster slightly higher frequencies (~5/second) and maintain that pace for a longer period of time compared to novices. When you think about the mechanics behind sprinting, it is easy to understand that a sprinter that has a high turnover stride (stride frequency) and is pushing off for more power (stride length) will elicit a greater speed.

One thing to understand, however, is that due to varying leg lengths amongst different individuals, stride length is difficult at times to train. Stride frequency, however, can be trained effectively to increase running speed.

Sprinting Performance and Stride Analysis

Below is a summarized list of the major muscular requirements during sprinting:

1. As the back (recovery) leg swings forward, eccentric knee flexion controls its forward momentum, prepares it for an efficient foot strike.

2. Muscle action then shifts from eccentric to concentric action and continues to the support phase (leg beneath center of gravity) which transfers power to the leg.

3. During the ground support phase, the high joint angle at the planted foot allows for stored elastic energy. Eccentric knee extensor activity also allows the quads to store and recover elastic energy.

4. There is a triple extension from the ankle, knee, and hip all at once allowing for propulsion and drive forward.

Training Goals

To maximize sprinting speed, I have listed a few training goals below that can help in running efficiency:

Minimize Braking - By aiming to plant the supporting foot directly beneath the center of gravity and maximizing the backward velocity of that leg during the propulsion phase will minimize the braking effect of forward momentum.

Fast Foot Strike - By increasing stride frequency and backward propulsion, you minimize the amount of time the foot has contact with the ground, therefore minimizing the braking effect of forward momentum.


Quote of the day:
"Formula for success: rise early, work hard, strike oil."
~ J. Paul Getty

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Day 36 - Go Fast and then Go Home

 

I probably sound like a broken record here, but unfortunately some people just don't get it. I see and get asked by people all the time why they are not getting/seeing results from working out an hour or more at a time. I then see them slowly jogging on a treadmill or elliptical.

Instead, why not try HIIT (high-intensity interval training) and cut your workout times in half? Chronic cardio should only be used if you are training for...wait for it...a cardio event such as a marathon or triathlon, etc.

Instead, most people can get into their gym, exercise using HIIT principles for 20-30mins and then be done with an even better workout than something that takes twice the time. A study done by McMaster University in Hamilton, Ontario, Canada found that men who performed sprint intervaltraining for a total of 2.5 hours (including recovery) over the course of 2weeks has the same results as the group who performed endurance training for atotal of 10.5 hours over the same time period.

Yes, its alright to go back and read that again. 1/5th of the time for the same results! Another study following a group of 15 women found that high-intensity exercise (40 to 45 minutes approximately four times weekly at a mean HR of 163 bpm) reduced body fat by about 5 percent over the course of 15 weeks versus a virtually unchanged percentage in the group that performed exercise at a lower heart rate (132 beats per minute).

I am generalizing in a very drastic way here, but think of the differences in body composition between an Olympic sprinter and an Olympic marathon runner. Both are 'thin' and very 'fit', however it is the sprinters that spend majority of their time doing, fast, maximum-effort exercise for shorter periods of time.

Quote of the day:
"It’s hard to beat a person who never gives up.
 -Babe Ruth





Running Speed

The mechanics involved in human running is substantially different than when walking. When human beings walk, the body rotates through various positions including balancing on one leg, while the weight shifts from one leg to both legs, to again on one leg. There is a cadence that rotates through these general positions.

Running, on the other hand, is more of a ballistic action with the body continually launching its weight from one leg to the other. The speed at which someone runs is directly linked to the stride frequency to stride length relationship. For example, when comparing novice to elite sprinters, studies have shown that elite sprinters achieve greater stride length and can increase it further up to about 45m from a static start of a race. Compare this to novice sprinters who peak their stride length around the 25m mark of a race from a static start.

When comparing novice to elite stride frequency, elite sprinters can achieve faster slightly higher frequencies (~5/second) and maintain that pace for a longer period of time compared to novices. When you think about the mechanics behind sprinting, it is easy to understand that a sprinter that has a high turnover stride (stride frequency) and is pushing off for more power (stride length) will elicit a greater speed.

One thing to understand, however, is that due to varying leg lengths amongst different individuals, stride length is difficult at times to train. Stride frequency, however, can be trained effectively to increase running speed.

Sprinting Performance and Stride Analysis

Below is a summarized list of the major muscular requirements during sprinting:

1. As the back (recovery) leg swings forward, eccentric knee flexion controls its forward momentum, prepares it for an efficient foot strike.

2. Muscle action then shifts from eccentric to concentric action and continues to the support phase (leg beneath center of gravity) which transfers power to the leg.

3. During the ground support phase, the high joint angle at the planted foot allows for stored elastic energy. Eccentric knee extensor activity also allows the quads to store and recover elastic energy.

4. There is a triple extension from the ankle, knee, and hip all at once allowing for propulsion and drive forward.

Training Goals

To maximize sprinting speed, I have listed a few training goals below that can help in running efficiency:

Minimize Braking - By aiming to plant the supporting foot directly beneath the center of gravity and maximizing the backward velocity of that leg during the propulsion phase will minimize the braking effect of forward momentum.

Fast Foot Strike - By increasing stride frequency and backward propulsion, you minimize the amount of time the foot has contact with the ground, therefore minimizing the braking effect of forward momentum.

Strengthen the Hamstrings - Eccentric knee flexor strength is the most important aspect limiting recovery of the leg as it swings forward.

-Tyler Robbins
B.Sc. PTS