Step Frequency Training Improves Running Economy in Well-Trained Female Runners

The purpose of this study was to determine whether a short training program to increase step frequency to approximately 180 s·min in well-trained female runners who had step frequencies likely to be suboptimal (176 s·min) would elicit improvements in RE. An additional aim of the study was to see whether a short training program could be effective in learning to run with a higher step frequency.

Variables that affect RE: hip joint angle, knee angle, step length, and step frequency.

Tartaruga et al. (43) found that 28% of the variability in RE could be explained by step frequency.

It seems that an optimal (i.e., most economical) step frequency of approximately 180 s·min21 is observed in elite distance runners.

de Ruiter et al. (38) found that both novice and trained runners self-selected stride frequencies that were, respectively, 9% and 3% lower than optimal.

Numerous studies have noted that spatiotemporal gait parameters affect RE.

What they did:

22 Female runners who had (a) a 5-km personal record time between 17 and 22 minutes within the last year; (b) been running regularly for at least 5 years; and (c) a current step frequency ,176 s·min21 were recruited for this study.

Experimental and control groups ran on a treadmill for 15 minutes for 10 consecutive days. The experimental group received step frequency training while the control group received no step training and ran at their preferred step rate. Before and after the 10-day training program, RE was measured at 2 velocities (3.4 and 3.8 m·s), and the groups were compared.

Before running, the foot switch was attached, and the metronome was set to 180 b·min and used to help subjects run at this step frequency. The foot switch equipped data acquisition system provided real-time step frequencies, and the subjects were cued if they needed to increase or decrease step frequency. Subjects were encouraged to remember each training session and try to replicate the 180 s·min during daily training runs that took place after the treadmill training session.

3.4 m·s is 7:53 mile pace (4:54 km) and 3.8 m·s is 7:04 pace (4:23 km).

Results:

• Increased their step frequency by 8.2% at 3.4 m·s and by 5.7% at 3.8 m·s.
• Increased their step frequency from ~165 to ~179 at 3.4 m·s and from ~170 to ~180 at 3.8 m·s.
• Significant changes in step length were observed at both running velocities as step frequency increased.
• 14.1% and 8.7% lower oxygen consumption values at 3.4 and 3.8 m·s, respectively, compared with the control group.
• Post-training oxygen consumption was 8.6%  and 3.2% lower than pre-training at the two velocities.
• HR was 4.8% and 5.4% lower in experimental vs. control at the two velocities, and this was achieved at a higher step frequency and lower oxygen consumption.
• Optimizing RE involves a complex combination of biomechanical, physiological, and neuromuscular components (2), and in this study, we sought to alter only one variable and, thus, simplify what a runner needed to concentrate on.
• After training and after running at a higher step frequency, a lower energy demand was most likely developed, whether it be through alterations in movement pattern that minimized wasted energy or through improved elastic energy storage and recoil. As a result of the lower energy requirements, the heart would not have to pump as fast to meet the oxygen demands of the working muscle.
• This method proved to be more effective than the POSE running technique at making runners more effective. POSE is considered the holy grail of running, but it involves a lot of variables. Changing too much too quickly leads to injury.

The coaches say:

• What’s your injury history? Swimmers tend to have muscular-skeletal issues. Sand would definitely exacerbate any problems there.
• Sand running will not help you become a more economical runner, because it has a huge ground contact time.
• It would be better for you to follow the protocol discussed previously to increase your cadence.
• Sand could cause achilles heel overstretching, which is no good.
• Trails would be great, but they won’t solve your problems. You don’t need technical running experience.
  • Hill intervals could be helpful to build leg strength.
• The best thing you could do would be a quality workout on the track.
  • Lucho would start you with 40s and 50s or strides (20-40 seconds).
    • Take a 20m buildup then sprint for 30-40m on a soft running surface.
    • This works on a pure nervous system level.
    • The key here is to NOT GO TOO LONG (less than 8 seconds at max effort; maybe less than 6 seconds).
    • Do 1 or 2 reps on your first time. You want minimal effective dose.
    • Don’t do anything you can’t handle. This is violent exercise!
• Tawnee warns about running in the hard sand at the shoreline where there could be a slope. This would cause muscular imbalances over time.
• If you have no injury history, Lucho and Tawnee recommend tempo intervals during your aerobic run at a little faster than 5K pace for 4-5x 30 seconds. It should feel fun, like you’re a little kid rearing to go. This shouldn’t have any recovery implications.
  • Alternatively you can end an aerobic run with a fast finish.
• For Olympic distance, you don’t need to do more than 90 minutes on the run. A 2-3 hour bike is ok.

Running Together

Brennan Fox

I have been struggling to find a good method to run with my partner when there is a significant speed difference between us (6:30 min/mi vs 10 min/mile).  I am curious if you guys have any suggestions for ways to run together where we can both get a good workout in. I bit more important info. My partner has a tough time running alone due to anxiety and although I regularly encourage her to train with others, she has not found any friends that she is comfortable running with since we have lived together.

The coaches say:

• Lucho thinks you should be a good partner and run with your girlfriend, but supplement that with extra running before or after.
• You’re going to be compromising yourself by altering your gait to run slower, but so be it. Be cautious, but at the end of the day, it’s important to be a good partner.
• Alternately, you could go to the track together and run at different paces but still be within .25 miles of each other.
• If there’s a flat, barren road where your girlfriend feels safe, you can run at different speeds but still be in sight of each other while doing out-and-backs.
• Consider getting a dog as a running buddy for protection.

Breathing Techniques 

Keith Mason

I saw a youtube video recommending a two nose in two mouth out belly breathing while running. Any thoughts? I do 3 miles technical trail on Tues, either 6 200m sprint intervals or 6 100m hill repeats on Wed, 4-5 miles on Friday and 8to -10 miles on Sunday.( working up 13 )  Had angioplasty April 25 to clean out the artery in my right leg and am running much better. I mow 3 lawns a day Mon- Fri.I do 30 min mobility on Mon, Thurs and Sat. I’m trying to work in two days of strength work but not sure when, as I don’t like to lift the night before I run. I’ve tried to lift Sunday after my long run, but It’s tough. I’m 82. Thanks, Kieth Mason, Georgetown, TX

The coaches say:

• Lucho’s never been a huge fan of this breathing technique. Why were they recommending it? If you need to breathe, then breathe. Especially on hill repeats and any kind of hypoxic training.
• You might consider playing around with this technique on easy 3 mile aerobic runs.
• It’s worth a try to see if it helps you. If it does, great. If it doesn’t then don’t do it.
• If you’re thinking so much about your breathing that you start messing up other things, then you’ll run into problems.
• If you really want to focus on breathing, try focusing on your breath during meditation or in regular life (even when you’re mowing lawns!) How you breathe outside of running will impact how you breathe during the run.
• Lucho recommends this kind of breathing when you’re done with a hard workout to help get back into parasympathetic mode. Belly breathing is very helpful to calm your system down.