Before we get into it, I want to elaborate on the title. When I say “safer”, I don’t just mean avoiding the immediate injury.This being a HIT influenced crowd, that’s always been a concern of HIT literature.
It’s not like this is a Cross fit convention.
I’m also referring to avoiding the wear and tear that adds to a chronic condition. The arthritis, bursitis, tendinitis, degenerative disc, patella femoral pain, etc. Because while those conditions may also come from things unrelated to exercise, it is the same set of joints, so I want to make sure my instruction doesn’t add to it.
Now for my own workouts, and for my clients, I’m probably a bit overprotective with the joints, even at the expense of some marginal benefit, due to my own ruptured biceps and triceps and various aches and pains from four decades of exercise and a semi-active, physical lifestyle. I understand if you’re an athlete or a bodybuilder or even just exploring different fitness options that you may not have the same priority. If it’s not a problem with you, it’s not a problem. I’d just say if at some point your joints do start to hurt, or if you want to get ahead of the inevitable joint issues that come with aging, you might find something useful here.
Let’s start with the 45 degree back extension. By the way, take out your smart phones and ipads and go to congruentexercisedotblogspotdotcom for the outline and slides.
45 degree back extension. Start short of hyperextension: straight knee, straight hip, torso in line with thighs. Start to lower the torso without rounding the back. At some point you’re going to feel a tightness in the hamstrings. The weight of your torso is pulling your pelvis into a tilt, which means your hamstrings are stretching over your knees and your pelvis. If you continue to lower your torso, your back is going to round because your hamstrings are locking your pelvis in place.
Reversing the lumbar curve is not a good idea, at least acc to the A&B texts, which emphasize the importance of the spine curves in disc health. So, once you feel the stretch in the hamstrings, you can either use that as a marker to begin the positive, or you can break at the knees to free up the pelvis, and continue to lower the torso. Either way you want to maintain the curve in the lower back.
This not a great exercise to try to progress dramatically in weight because of the spine and the positioning of the hamstrings. A better way to approach this is as “practice” for proper spine mechanics, and use the next exercises for progressive glute and hamstring work.
(How to handle the Medx question IF ASKED: the anatomy & biomechanics texts are very clear that the safest position to load the spine is in its natural curves. So my approach for most exercises is to try to keep those curves, especially when other joints and muscles complicate the exercise. I’ll defer questions about isolated lumbar extension to others more familiar with it, other than to say that as long as you avoid the anatomic stops, you’re probably going to benefit.)
The clamshell floor exercise is suggested in some back therapy as a way to re-engage the glutes. This machine mimics the joint position of the clamshell.Pretty straightforward, but I have a tweak to add. You may notice in the course of a set, early, the pelvis stays in place and the movement arms move. When approaching failure, and the movement arms stall, the hips tilt, the belly protrudes, the lower back curve gets exaggerated. The contraction of the glutes, instead of pulling the legs towards the hips, pulls the pelvis towards the legs.
Defeating the purpose of the exercise, which is to train the glutes without stressing the spine.
My tweak is to raise an inch off the seat by pushing on the foot bars, so the hamstrings lock the pelvis from the rear bottom, and to tighten the abs to lock from the top front. This way, as the glutes approach failure, you don’t extend the set at the cost of the lower back.
I do the same with the adduction, although the tilting/arching isn’t as prominent. Notice in the diagrams of the adductors, and then the hamstrings, that the medial part of the hamstrings pulls in the same direction as the adductors. Try doing the adductor immediately after the leg curl to see how much your performance in the adductor is affected by the hamstrings.
Seated leg curl If you try to do this with a fully extended knee at the start, you run into sufficiency issues affecting the curve in your lower back again. Hamstrings go taut, which pulls the pelvis into a posterior tilt, which flattens the lumbar curve. As you curl, the pelvis frees up, the lumbar curve returns. And vice versa. This flattening-curving of the lumbar under load puts extra stress on the discs that I’m trying to avoid.
I would start short of full extension, set the curves in your back and hold them through the knee flexion. At the finish, lift your toes to keep the gastroc from cramping. Depending on the brand, you may have to “bench press” to keep your hips from sliding forward at the finish.
Note the finish. This is a sharper knee angle than I’m going to suggest for the leg extension, mainly because there is no knee cap behind the knee.
Leg extension 2 issues with the leg extension: where you start, and where you finish. Both have to do with the knee. The kneecap functions as a pulley. You can live without a kneecap, but your legs won’t be very strong. The muscles of the quad come together in the tendon, the knee cap is in the middle of the tendon, this creates an internal moment arm, so the strength of your quads is amplified. The knee cap keeps the line of force of the quads away from the center of the knee. The issues start when your knee is bent less than 90 degrees; the force from the quads and the resistance from the shin pulls the knee cap towards the center, compressing everything internally, which at some point gets irritated and turns into a symptom (like pain). This is an easy fix; just start with the knee opened enough to avoid the pain. Now the kneecap deflects the forces rather absorbs.
Where to finish. Way back, used to try to straighten the knee as far as possible, and it did burn, so we thought it was right. Turns out, something called “terminal rotation” or “the screw home mechanism” at the end of the range, which is the tibia rotating on the femur creating a bony lock. This bony lock is supposed to be passive; allows us to stand or walk with relatively little muscular effort. So there doesn’t appear to be a good reason to force your knee into that lock, because a) you’re working against your own joint, and b) peak torque for the quads is closer to 70 degrees than 0 degrees anyway. Is there a downside? May be no, certainly not as much as the start position.
(What about “Terminal Knee Extension” as done in rehab? What about leg extension machines with drastic fall off? In rehab, they use “TKE” with a cuff or cable as a way of avoiding the compression in the knee. Also to “wake up” the vastus to help stabilize the knee. What can happen is the knee cap goes out of alignment either from an injury or flat feet or whatever, and the biggest of the quads, the RF, continues to pull it out of alignment. The point of TKE is to position the RF so it can’t pull as hard, leaving the vastus to do the work. It’s de-emphasizing the RF and engaging the vastus that is the point, not just jamming the knee into full extension. A leg extension machine that challenges the joint angle for peak muscle torque, but then shaves the cam to allow lockout, still doesn’t shut down the rectis femoris at lockout, it just allows you into the screw home mechanism. Which may not be harmful, but doesn’t accomplish the same as the rehab “TKE”.)
Barbell Bench Press Most important from a safety perspective is the finish. Pectorals, triceps, delts exhausted, bar over your face, and to replace the bar you have to hunch your shoulders forward/protract your scapulae, which uses the small, fine serratus muscles on the side of the ribs. And the consequences of missing the put back are disastrous. So in this case, the last reps aren’t the safest.
So if you don’t have 2 more spotters, hold back a bit in the set, and use a set extender: manual resistance chest press or pushups, so the total set is about a minute.
If you’re going to use a machine. I suggest the lower grips, not because of the grip but the shoulder angle. You could use the bar grips with a higher seat to affect the same angle. I also suggest “keep your hands in your peripheral vision” to avoid overstretching the shoulder.
2 slides of the shoulder joint, the bones and the ligaments. You see how much is packed into that small area, the head of the humerus, the A/C joint, the coracoid process, various bursa and ligaments, capsule, as well as the rotator cuff, and biceps and triceps tendons. In neutral, as in the diagram, everything fits, but at the extreme positions movement is stopped by everything coming in contact. If you load those positions with external weight, that contact can be become an impingement, with various ailments that follow.
As a general rule for upper body work, looking straight ahead, keep your hands in your peripheral vision. This gives a little margin of error while still giving enough range for the muscle to work. Same applies to chins and pulldowns.
Assisted Chin Re; the effect of grip. Try doing a parallel or close grip chin up or a pullover machine immediately after training chest to failure, you’ll see how much your performance on the chin up is affected by the pectorals. So for a beginner, someone with low starting strength, that I don’t want to discourage, I start them with a closer grip on chins, so that they can do any reps. As they get stronger, maybe they stall on the progression, I’ll move them to the wide grip, so there are fewer big muscles helping the lats.
For someone advanced, may go the other way, the first set wide, the next close, as a way of extending the sets.
Let me conclude by saying that I am stunned at where the commercial fitness industry is today. I’ve been looking at this stuff for 40 years, and part of the Nautilus influence on me was that the workout shouldn’t cause its own injuries. It’s one thing to get injured on the field, it’s another to get injured in the weight room preparing to get on the field.
So to see the popularity of Cross Fit and Insanity and Biggest Loser, all of which have a callous disregard for careful exercise blows my mind. Fortunately for us, the HIT influenced, I think the vast majority prospective clients want no part of getting injured by their workout.