Leg Extension machine

[boxus]

Originally Posted by AstralProjection

that's only you, maybe someone else here knows, you can't speak for everyone, only speak for yourself

No one here should be giving such medical advice, matter of fact, almost all exercise and especially strength training forums specifically ban doing it.

And yea, it was only me, that is why I stated "My posts are for non-injury/non-medical issues only."

And yes, no one can give you medical advice, they have not examined you to see what is wrong with you.

[Suburban_Guy]

There are countering opinions out there that leg extensions aren't necessarily as evil as some automatically portray them as.

Tip: The Real Science of Leg Extensions

Indeed, tensile forces are placed on the ACL during the knee extension exercise. However, when examining these forces, remember that they exist on a continuum, and injury is not a concern until a certain threshold is reached. For the ACL, this threshold has been reported to be upwards of 2,000 N, depending on an individual's age. So the tensile forces experienced by the ACL during the knee extension (158 – 396 N, using loads ranging from a dynamic 12 repetition-maximum to a maximum voluntary isometric effort) are less than one-fifth of its ultimate strength.

ACL forces during the knee extension are less than or equal to many other "functional" tasks, such as walking or landing. Therefore, knee extensions do not appear to be any more unsafe for the ACL than what's required for everyday activity.

The recommendation of the squat being a safer exercise for knee ligament health is also logically inconsistent. For example, one study suggests that posterior cruciate ligament (PCL) forces in the squat are about an order of magnitude, or ten-times greater than those placed on the ACL during the knee extension. To put this in perspective, the PCL:ACL ultimate strength ratio does not approach such a difference (10:1) and is closer to 1.5 – 2:1. Thus, many of the arguments against utilizing the knee extension in healthy populations out of concern for ACL health are unfounded and logically inconsistent.

Is The Leg Extension Bad For Your Knees? (7 Studies Help Answer)

Many people use and have used leg extension machines with no issues. That's not to say everyone should do leg extensions. Some people just cannot for whatever reason. But that's the same for just about any exercise out there. Some people cannot squat, or bench press, or....

[boxus]

Yet...

https://www.t-nation.com/training/tr...leg-extensions