Ok, Physics gurus, please settle this debate(mech. advantage

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Please compare the 2 leg press devices shown in the following 2 videos.

First video features a male performing 1000 lb leg presses for 30 repetitions.

https://www.youtube.com/watch?v=917sv-SHFbg



Second video features a male performing 930 lb leg presses for 14 repetitions ON A DIFFERENT MACHINE.

https://www.youtube.com/watch?v=DRAg2_BkKu8


QUESTIONs: Which machine has the least mechanical advantage?

If one was to place 930 lbs on each device, which device would require the most work in order to complete 14 reps?

Thanks in advance for your answers.

First thing to note, when lifting you do not include the weight of the apparatus (unless it is the bar which happens to typically be 45 pounds). So he is actually lifting 990 LBs (assuming those are standard 45 22*45=990 pound weights which they are based on the math). However, The other video also exaggerates the weight. Assuming he has both sides set at 10 45 LBs He is lifting only 900 pounds. (of course he never shows the other side so i did not get a chance to check but I am willing to deduct points for him simply not showing and yes they do have thirty pound weights so its not unreasonable for him to have 30 on the other side but I did not see it.) So the difference in lift between the two videos is 90 to 60 pounds. The interesting thing about this is the difference in the way the weight is lifted in the first video the weight is a downward force applied along an incline plane, while in the second video the is applied to at least three simple machines (there is clearly a lever and a two of a secondary machine that i personally think is a wheel and axle. However, once again I can not see the actual machine to confirm the mechanism). The following Equations can thus be used to solve the problem assuming all variables can be derived (which i have not attempted yet so we may yet end in failure which is what i believe will happen for the time being due to the amount of work required on my part (benefit/cost analysis) Suffice to say this question will most likely require trig and geometry to solve in which case i will post what I do but not now).

Let lowercase letters be subscripts since i can not figure out how to get a subscript to stay sub-scripted in the post
First video:

MA=Fw/Fi=

or gravitational force of the load object on the plane over input force

Second video:
MA=M2/M1=A/B
where M1 = input and M2 = output

MA=Fb/Fa =A/B

Actually, I am going to stop here because i should have started by actually calculating for variables needed. Instead of going on a goose chase. Also, i have some one in mind who might be able to help finish this one.

I don't know if either machine has an advantage over another. Normally, they are all designed to do the same basic job.

Someone with more of an engineering background would have to examine the design of each setup to see if there's a difference.

Both men were in bad form. If you don't bring the knee to a 90-degree angle, you're not doing a full squat, so they both cheated to look good on the numbers. They probably couldn't do anywhere close to those numbers with a freeweight squat.