Brian Jackson
Platinum Member
- Joined
- Jul 17, 2004
- Messages
- 3,543
- Location
- Hamburg, New Jersey USA
- Aircraft
- GyroBee Variant - Under Construction
How to push-mow a lawn without getting tired
Granted the title is a subjective term, but today I waited until the highest heat with near 100% humidity to try out my theory. We have a flat lawn that spans 2 city lots. My push-mower is heavy and self-propelled, but I disengaged the self propulsion through this entire mowing as not to taint the results.
Furthermore, I should do this many more times before reaching a hypothesis, but I don’t feel like it. Maybe later. I mowed a strip down the measured middle and proceeded to mow one side as usual, ending up nearly exhausted and dehydrated. I then immediately mowed the other side using a different technique.
Hypothesis:
Less energy is expended by using gravity and compression in creative ways.
First half:
Mowed in the “traditional posture” with elbows half-bent and each knee/ankle straightening itself in sequenced stride to provide forward motion.
Second half:
Elbows and knees locked and ankles only bent when needed to compensate for irregularities in the terrain.
Findings:
I was completely done in during the first half of mowing by exhaustion. I should have listened to my wife… I had to stop several times to collect my breath. It was no fun.
I was able to mow the 2’nd half with little effort beyond lack of creature comfort. I never felt the heart race of over-exertion. Truth is it was much easier than mowing the first half. Here’s why.:
Sustained force over half-bent arms requires muscle power to remain half-bent. One must resist further bending. Locking your arm bones in a straight line requires no muscle power to remain that way. All forces are in compression.
Because of this, you don’t need to “push” the mower. Lock your arms and simply lean forward… gravity will do the rest. The resistance felt is that of grass, friction and vectored forces by the terrain. Keep your knees straight and take smaller steps. That keeps the potential forward energy within a narrower margin.
I kept my joints mostly straight, expended little energy “pushing” anything, leaned forward and followed it up with leg strides that were more “scuffs” than lifting my legs. When conserving energy don’t do any more work than you have to.
Based-Theory:
In a practical sense, when doing actual work, use your skeleton. Using Newton’s first law of thermodynamics, it appears to be much better at distributing heat/energy than bio-chemical. I used myself as an example, but I was bordering on a heart attack otherwise.
Follow-Up:
Do not call me or email me for any reason. I really wanted to be at Mentone yesterday but could not. I'll explain later.
Respectfully,
Brian Jackson
Granted the title is a subjective term, but today I waited until the highest heat with near 100% humidity to try out my theory. We have a flat lawn that spans 2 city lots. My push-mower is heavy and self-propelled, but I disengaged the self propulsion through this entire mowing as not to taint the results.
Furthermore, I should do this many more times before reaching a hypothesis, but I don’t feel like it. Maybe later. I mowed a strip down the measured middle and proceeded to mow one side as usual, ending up nearly exhausted and dehydrated. I then immediately mowed the other side using a different technique.
Hypothesis:
Less energy is expended by using gravity and compression in creative ways.
First half:
Mowed in the “traditional posture” with elbows half-bent and each knee/ankle straightening itself in sequenced stride to provide forward motion.
Second half:
Elbows and knees locked and ankles only bent when needed to compensate for irregularities in the terrain.
Findings:
I was completely done in during the first half of mowing by exhaustion. I should have listened to my wife… I had to stop several times to collect my breath. It was no fun.
I was able to mow the 2’nd half with little effort beyond lack of creature comfort. I never felt the heart race of over-exertion. Truth is it was much easier than mowing the first half. Here’s why.:
Sustained force over half-bent arms requires muscle power to remain half-bent. One must resist further bending. Locking your arm bones in a straight line requires no muscle power to remain that way. All forces are in compression.
Because of this, you don’t need to “push” the mower. Lock your arms and simply lean forward… gravity will do the rest. The resistance felt is that of grass, friction and vectored forces by the terrain. Keep your knees straight and take smaller steps. That keeps the potential forward energy within a narrower margin.
I kept my joints mostly straight, expended little energy “pushing” anything, leaned forward and followed it up with leg strides that were more “scuffs” than lifting my legs. When conserving energy don’t do any more work than you have to.
Based-Theory:
In a practical sense, when doing actual work, use your skeleton. Using Newton’s first law of thermodynamics, it appears to be much better at distributing heat/energy than bio-chemical. I used myself as an example, but I was bordering on a heart attack otherwise.
Follow-Up:
Do not call me or email me for any reason. I really wanted to be at Mentone yesterday but could not. I'll explain later.
Respectfully,
Brian Jackson
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