ATC 354: The Science & Art Of Stroller Running – A Guide To Maximizing Your Time and Effort When Pushing Precious Cargo
June 30, 2023
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On this episode of Ask The Coaches with Tawnee & Lucho we take a deep dive into stroller running presenting the current research on this exercise and how that blends with practical, real-life application especially for endurance athletes who are going long!
Laura asks
Everything Stroller Running
My question is all things stroller running. One) what does it do to your body in a positive or negative regard (biomechanically speaking and energetic cost)? Is there specific strength training that will help? I constantly battle with sore intercostal muscles and out of alignment in my ribs/shoulder etc on my right side because I only push with my right arm. I have no control and it doesn’t feel safe with my left arm. Are there specific workouts that I can do with the stroller that will help my overall fitness or is running with the stroller enough. I guess I’m pushing right around 60lbs right now.
Also for my Question… workouts/ideas to increase speed. I’m current running 6-10 miles at a 9:15 pace avg HR is 151. I run hilly roads. Doing 2-4 stroller runs a weeks I’d say maybe 20% is above 160 bpm,
15-20 miles a week total.
When I race with the stroller about half the time, 47%, my HR is 158-165 and 5% above 165.
Training for 50k this fall.
What the coaches say:
Our top takeaways for stroller running
- Fixed front wheel always (we use the BOB, but many good brands!).
- I prefer one-handed running somewhat alongside, which seems to feel the best and most natural especially for longer runs.
- However, on hills (up or down)—double handed grip seems more secure.
- Use a wrist strap! Both sides even! Buy one (or additional one) if this is an issue when switching hands.
- Don’t hunch or round shoulders over bars.
- Don’t bend at the hips (ie folding body).
- Posture! Shoulders down and back, hips forward within reason (ie don’t lean back)—but still relaxed and loose.
- Personally I like the bar to be at a height that allows for about 90 deg at elbow.
- Most importantly, run in a way that feels most comfortable *and safe* for you and your child. There is no consensus on this topics and research is lacking for practical applications.
Addressing the intercostal muscle soreness & strength recommendations
- Intercostals – small muscles between the ribs
- The internal intercostals assist with exhalation by drawing the ribs downward and decreasing the space of the thoracic cavity.
- The external intercostals draw the ribs upward, increasing the volume of the thoracic cavity.
- Focus on core, diaphragmatic breathing (no shallow chest breathing), shoulders – serratus, lats, T spine mobility/strength
- Issue of rotation and twisting? And posture – hunching
- Exercises and movements:
- Mountain pose – Tadasana, contract at the end of inhale, contract at the end of exhale
- Supine spine twist, windshield wipers, pretzel
- Incorporate ROM exercises for trunk rotation to avoid adaptive stiffness
- Hip flexor exercises
- Healthy shoulder work/balance
Stroller running biomechanics article
- Take a wide grip, both hands, and push down slightly
- Bar is below waist! Shoulder-width grip, arms nearly straight
- When my foot is landing, I push down on the handle bars, just a bit, to “cushion my fall”.
- Run with a high cadence (take short, quick steps)
- Similar to what is seen in research on this topic!
- I typically run the stroller with a cadence of 100-105
- Long stride leads to quicker fatigue in this scenario he says
- Lean forward slightly
- promotes great biomechanics, i.e. foot lands below your body, naturally positions your upper body over the handle bar
- Do not swing arms (use a subtle torso rotation)
- One hand asymmetrical – right and left side of your body are loaded differently. This could lead to imbalances and/or injuries.
- Torso rotation requires minimal energy—this contributes to the “cheating” concept.
Current jogging stroller science & research articles with summaries*
*not an exhaustive list of available research on this topic
Run kinematics with and without a jogging stroller
- Study basics:
- 15 healthy adult recreational runners, no experience with stroller running
- 10kg weight in stroller
- 10 trials (5 with stroller)
- 3D kinematic analysis
- 16m indoor run (that was it!)
- Overall changes in biomechanics were small—conclude that more research needed to see if these changes persist, worsen or self-correct with time/experience.
- Also these runners were NOT running fatigued.
- Trunk kinematics changed significantly when running with the stroller. Forward lean was increased by 6.78 compared to independent running [95% CI (98, 4.68), p < 0.001]. Total trunk rotation in the transverse plane was significantly decreased by a mean of 11.48 [95% CI (14.88, 8.28), p < 0.001]. There was a significant decrease in trunk movement in the coronal plane of 2.98 with the stroller [95% CI (0.88, 4.98), p = 0.009].
- Anterior pelvic tilt was increased by 2.88 with the stroller; associated with a significant decrease in peak hip extension of 38 [95% CI (4.48, 1.58), p = 0.001] and an increase in hip flexion at initial contact of 2.68 [95% CI (1.38, 3.88), p = 0.001].
- This is correlated with injury and lumbo-pelvic hip complex and low back pain, due to increased lordosis and impingement of vertebrae – though lordosis not increaesd in the stroller running due to voerall increase in forward lean
- Work on hip flexor ROM mobility – tight!
- Knee flexion increased and ROM of knee in saggital plane decreased, but not significant
- No effect on ankles that reached significance
- Analysis of findings
Stroller running: Energetic and kinematic changes across pushing methods
- Only 800m, self-selected pace, not hard running.
- SR = stroller running.
- Sixteen individuals (M/F: 10/6) ran at self-selected speeds for 800m under three stroller conditions (2-Hands, 1-Hand, and Push/Chase) and an independent running control. Strollers loaded with a 16kg weighted infant model in order to simulate the presence of a 3 year-old child.
- the purpose of this study was to investigate the energetic and kinematic effects of 1) stroller running compared to running independently, and 2) commonly used pushing methods used during stroller running in recreational runners.
- Pushing method had a sig effect on speed but not HR or energetic cost.
- Changes in lower-limb kinematics were observed, as SR significantly shortened stride length in comparison with Non-SR.
- A significant decrease in speed (p = 0.001) and stride length (p<0.001) was observed between the control and stroller conditions, however no significant change in energetic cost (p = 0.080) or heart rate (p = 0.393) was observed. Additionally, pushing method had a significant effect on speed (p = 0.001) and stride length (p<0.001).
- Given that 69% of our participants and 51% of the observed stroller runners on public paths all preferred the 2-Handed SR, it seems this is an SR condition that results in the least perturbation of typical running behavior.
- Stroller running calculator:
- The models suggest that when speed is maintained, running with a stroller increases cost between 5–8% depending on the pushing method. As expected, the 2-Hands method is the most economical and the Push/Chase method is the most energetically costly. To predict the cost of a runner of a different mass, please go to https://tinyurl.com/stroller-running-calculator.
- Also noted in this study that: few studies have investigated biomechanical responses specific to SR, and there is no current consensus on how running speed and stride length are affected. Most recently, O’Sullivan et al. [8] and Smith et al. [6] observed no difference in stride length or running speed during SR compared to independent running, yet prior work by Brown et al. [5] noted changes in stride length. Differences in study design may have contributed to these confounding speed, stride length, and stride frequency results.
- More findings on grip type:
- Of the 16 participants, 11 preferred the 2-Hands, 4 preferred Push/Chase, and 1 preferred the 1-Hand SR condition to the other SR conditions.
- The Push/Chase and 1-Handed SR methods are the most disruptive to running kinematics, while the 2-Hands method results in a speed and stride length most similar to Non-SR.
Physiological and biomechanical responses of running with and without a stroller : sport and physical activity
- These women did run hard
- In this: 8 experienced female runners, self-paced 2.4 kilometre (km) running trials while pushing (JS) or not pushing (CON) a stroller on a concrete sidewalk. The time to complete the 2.4 km run was not different between JS and CON (687 ± 30 versus 660 ± 18 seconds).
- Mean steady state HR (173.0 ± 5.0 versus 167.0 ± 5.1 beats / min) and oxygen consumption (VO2) (40.1 ± 3.1 versus 36.1 ± 2.8 m l / kg / min) were higher (p<0.05) in JS than CON, respectively.
- JS resulted in a greater (p<0.05) number of steps taken (1969 ± 78 versus 1886 ± 74) and reduced (p<0.05) step length (1.24 ± 0.06 versus 1.29 ± 0.06 metres) compared to CON.
- The use of a JS resulted in an approximate 4% increase in HR and an approximate 11% increase in VO2, perhaps due to changes in the normal running stride pattern and the application of an external load from the jogging stroller.
Physiological and biomechanical responses while running with and without a stroller
- The longest run trial we could fin that was studied: these subjects ran 30 MINUTES.
- The 1st field test involved running at 75% VO2max for 30 minutes without a stroller and the 2nd involved running at the same speed with the stroller.
- These results indicate that pushing a stroller affects some indices of exercise intensity while running. Gait does not change. These data do not support an association between stroller use during running and an increase risk of orthopedic injury. Further studies should examine these variables at lower intensities that are run by most recreational joggers.
The metabolic cost of human running: is swinging the arms worth it?
- “Our findings support our general hypothesis that swinging the arms reduces the metabolic cost of human running. Our findings also demonstrate that arm swing minimizes torso rotation.”
Energetic Cost and Kinematics of Pushing a Stroller on Flat and Uphill Terrain
- “The increase in energetic cost of pushing the stroller was approximately threefold higher uphill than on the flat incline, and women were influenced more than men when running uphill at the highest speed (all p < 0.05).”
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