Squat, Press, Extend or Flex for Strong Legs & Healthy Knees, Pt. 4

As we conclude this series of Squat, Press, Extend or Flex for Strong Legs & Healthy Knees, we shift the focus from learning the internal components of the knee along with the most common injuries to the staple exercise selections that are generally chosen by most fitness trainers and coaches alike.

Let’s start by presenting the choice of using “Open versus Closed Kinetic Chain” movements. In lay terminology, “Closed Kinetic Chain Exercises” (CKCE) are those in which either the legs or arms are in constant contact with the floor or stable platform and therefore immovable such as in a squat or push-up.

“Open Kinetic Chain Exercises” (OKCE) are those in which the hands or legs are free to move while pulling or pushing a resistance such as in a leg extension or bench press. So the question, which has caused quite a bit of controversy in the industry over the last several years, is whether we should use open or closed kinetic chain exercises to strengthen the leg muscles. Which, in turn, offer greater knee stability and health.

Fig. 1: The major muscles of the leg

Without getting too caught up with trying to name all the different machines that can be classified as both CKCE or OKCE, I’m going to focus on the good old foundations of human movement and staple gym equipment.

Closed Kinetic Chain Exercises

The Squat: Considered by many to be the most functional movement ever imaginable since in fact it is nothing more and nothing less than sitting and standing. This is the best exercise that should be performed if and when the mechanics are correct and the client can at least perform a simple body weight squat without contraindicated pain. Keeping in mind that if any existing knee problems exist there may always be some type of discomfort. As fitness professionals we must learn and know how to counsel the client on discomfort that needs to be worked around, as opposed to the pain that can be associated to that of a sharp, stabbing pain, which means STOP.

Many times, we will hear a client complain of a knee problem and the first thing that someone feels he or she shouldn’t perform is a squat. My first question to that client then becomes: “Did you sit down and stand up today? If so, how many times?” Clearly, the average general fitness client will answer “yes” with at least 10 to 20 times in a 24- hour period. The problem is solved. You can now educate your client on how he or she currently squats repeatedly on a daily basis as part of the activities of daily living (ADL’S), while most likely he or she didn’t even remotely see it that way.

The job of the fitness professional now calls for an analysis of the movement, the detection of any imbalances or issues and the subsequent creation of the exercise prescription. In short, the most critical things to look for during the performance of a squat are knees traveling over the toe, alignment of the knee staying in line with the foot during performance, hip range of motion (ROM) and core stiffness including the erector spinea, ilio costalis lumborum, and longigissimus dorsi.

Fig. 2. Muscles of the Back

Leg Press: The second exercise on my list of CKCE’s is the leg press. Although not as demanding as the squat due to the stabilized nature of the laying position, it is the second most complete and safe exercise for the lower body and strengthening the knees. Generally speaking, once a client has gone through the basic progressions of learning technique and creating efficient energy pathways, our goal as fitness professionals is to create an environment of adaptation. Often referred to as the Overload Training Principle, a state of adaptation involves the execution of a movement at 100% intensity for the ultimate goal of hypertrophy. On the same note, 100% intensity with the focus on hypertrophy is more efficiently achieved with maximum stability such as what can be experienced on a leg press.

As with the squat, the basic principle to keeping the knees safe during the performance of this exercise is to make sure that the knees don’t travel over the toe and that the knees don’t buckle in upon the upward pushing phase. Tempo should be controlled with no locking out at the top end of the range of motion. Any visible ballistic bouncing at the bottom should also be addressed.

Lunge: My third exercise on the list of CKCE’s is a lunge. The lunge is as associated with ADL’s as the squat is in the way that it mimics, in a lot of ways, the act of reaching forward to pick something up off the floor as you leave one foot back and move one forward as in to step and reach. As with any exercise, choosing the correct application, load, speed and movement pattern must be adjusted per the clients current level of fitness or post-operative progression. With any beginning client, the protocol should always be to move into a lunge after mastering a body weight squat, or, if needed prior to a squat or leg press. A leg press would still allow a client who cannot yet support his or her body weight to perform a compound movement with less than his or her own body weight.


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About the Author

Felix Doval is the founder and owner of Pro-Active Wellness, a leading South Florida Health and Fitness education provider whose curriculums are taught using the private training facilities of Active Bodyz Fitness Training, located in Davie, FL.

Felix holds a Master Certification with the NFPT, and is NSCA and NAHF certified.


These resources are for the purpose of personal trainer growth and development through Continuing Education which advances the knowledge of fitness professionals. This article is written for NFPT Certified Personal Trainers to receive Continuing Education Credit (CEC). Please contact NFPT at 800.729.6378 or [email protected] with questions or for more information.
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