Assistance exercises, also known as accessory work, usually aim to fix weaknesses. They may correct imbalances or improve a weak portion of the range of motion for a big exercise. This would suggest that assistance exercises will repair weak links in a chain.
Perhaps you want to focus on a muscle. You may want more volume and blood flow for it too. This could build more muscle, help with recovery, or prime the muscle for another exercise. You may achieve some result without asking too much from your body as a whole if you choose the right one. This would suggest assistance exercises can boost development beyond the mainstays.
You may use them to beat plateaus by confusing the muscles through variety.
If you just squat, bench press, and pull-up, it is implied that these alone will not develop you completely.
The mere existence of assistance exercises seem to show that the core exercises are not enough. This is wrong for good reasons. You should instead apply the big multi-joint exercises only and never add assistance exercises.
If a proper selection of exercises is made, then only a few movements are required to develop almost the ultimate degree of strength and muscular size.
– Arthur Jones
- They may support isolation exercises.
Assistance exercises often try to build up a specific muscle. The body works as a unit and not as bits and pieces though. Isolation exercises will…
- reduce tension.
- harm the joints.
- allow for poor joint angles.
- work less efficiently.
- have poor strength curves.
- maximize shear over compression.
Turning a good compound movement into a bad one by giving it isolation properties ruins it. For example, the close-grip bench press aims to isolate the triceps. Instead, this increases shear force on the elbows and can harm the shoulder too. You may feel it more in the arms due to more relative work and blood flow but the results will drop.
Choose a medium grip bench press. This addresses the chest, shoulders, and triceps evenly. It allows the triceps to grow without the joint stress. It also increases tension, the main stimulus for strength and size. Any deviation away from medium, safe grips and stances will endanger the joints.
- They may support machines.
Machines allow you to assume positions you would never load through gravity in real life. They also fail to give you complete control over the movement. This reduces results and safety.
- They may allow partial movements.
Partial movements maximize leverage but reduce the stimulus to the muscles.
Muscles fibers run from attachment to attachment. This means that during a squat, the same muscle fibers in your quads work at the top versus the bottom of the movement. The only thing that changes is the muscle length. The ideal muscle length for tension is in the middle.
The relative contribution of muscles only change during uneven lifts, such as on a barbell deadlift. These are bad exercises anyway. They favor a group of muscles too much, which gives the exercise isolation properties.
- They may overemphasize stabilizers.
Unilateral exercises and partial movements tend to work small stabilizers more than needed. Stabilizers have a limited capacity for growth and exist to support the large muscles. Focusing on them with heavy weight lessens stability and makes a good exercise worse.
- They may support accommodating resistance.
Accommodating resistance means changing how heavy the weight feels throughout the range of motion. This often means making it harder at the lockout. This fails to adhere to the length-tension relationship. Accommodating resistance in the form of chains, bands, and machines goes against our bodies’ expectations. Muscles work best in the middle, not at the endpoints.
- They justify variety in general.
Variety for its own sake serves no purpose. The body does not adapt to specific exercises, it adapts to the same stimulus. If you increase weight or get more reps then you change the stimulus. Cardio is the better area to include variety if even desired.
- They may separate strength training from muscle building and vice versa.
- They may divide strength into many divisions involving various speeds.
Strength and speed are different qualities but improving one improves potential in the other. The idea of training an exercise done heavily with lighter weights for speed makes no sense according to the force-velocity relationship. The best way to train with heavy weights will always be training with heavy weights, and that alone due to specificity.
- They may overemphasize the idea of central nervous system (CNS) fatigue.
Little movements are less stressful on the system. Every movement exacts a cost though by taking resources that should go toward recovery on exercises that truly matter. CNS fatigue comes from overtraining, not from relying on the best exercises. Overtraining comes from some combination of too much, too long, and too often. Using the same good movements over and over again will not overtrain you. Abusing these good exercises with not enough recovery will.
- Smaller muscles that act weakly contribute less, not limit.
Weak muscles will not limit a big movement with the exception of a major injury. All muscles involved in an exercise contribute, with the largest ones in a movement doing the most. The body does this as an energy conservation method.
The idea that the lower back could limit you in squats is horribly stupid. The large muscles of the hamstrings, glutes, and quads will always limit the squat. The core merely transmits forces and the lower back should never fail with good form.
Weaknesses may come from disuse but the body uses other muscles as compensatory measures. This temporarily reduces your performance and ability. If you persist in using the normal movements though then the weaknesses get better.
Why do something dysfunctional to correct something functional? Why not just do a functional task at a lesser level until the weakness improves? If you injure your quads just squat with less weight. Avoid leg extensions for them or bad exercises for the hips, such as the hip thrust, in an attempt to work around the injury.
The best way to correct a weakness is patience and the right exercises. The lagging muscles will catch up. Avoid trying to make a right with a bunch of wrongs.
- They may overemphasize bodyweight and so-called functional work.
Assistance exercises often place a special status upon bodyweight work or so-called functional exercises like kettlebell swings. Bodyweight training has no special advantage over free weights. Resistance is resistance. Do not focus on these unless they work best for building muscle and strength or getting your heart rate up for cardio.
- They may allow unsafe exercises.
Many unsafe exercises such as front squats, box squats, and overhead presses come under this realm. They may place shear on the knees, compress the spine, or cause shoulder impingement. They may have unique problems or otherwise harm you according to the reasons listed.
Ignore the Assistance Exercises
Any exercise that works a muscle with tension can build size and strength. Assistance exercises can certainly work to build muscle. Although they can work, a simple push, pull, and squat work much better.
We can only perform a small set of exercises safely with heavy weights. Use exercises that develop all the major muscle groups evenly. Choose medium grips and stances. This will keep you injury-free and allow tension in all the involved muscle groups. You will also focus on what matters with this approach. This improves recovery and allows much faster results.
Learn good form on the big three and make progress. Weaknesses will correct over time and all the major muscles will contribute their share. Avoid assistance exercises.