These exercise variations will tax you, frustrate you, and cause you great discomfort. But most of all, they'll make you a far better lifter. Why? They all involve the use of unstable or "oscillating" objects.
Lifting unstable, shaky things works to improve your motor control and stability. It also improves your intermuscular (within a muscle) and intramuscular (between different muscle groups) coordination and overall muscle function. In short, this method of training will make you better at just about anything.
Double Javelin Press
The javelin press is an exceptional overhead pressing variation that requires a combination of strength, stability, coordination, and skill. However, with enough practice, many lifters can learn to cheat the system by becoming neuromuscularly efficient at lousy form, as they learn to stabilize the load with faulty mechanics.
For this reason, you should use the double-arm javelin press as it exposes the undesirable neuromuscular adaption. It's one thing to control a single, unstable object as every bit of neural drive can be channeled to that individual side. However, locking in two barbells overhead requires precise execution and textbook mechanics. There's no cheating the system on this one.
Bottoms-up movements are some of the best exercises for improving motor control, joint stability, reciprocal co-contraction, and overall movement mechanics. You're forced to center the glenohumeral joint into the optimal position in order to control the unstable load. Bottoms-up movements also teach you how to produce perfectly vertical force vectors against a heavy load. Any lateral or horizontal deviations result in an immediate failed attempt.
If you've ever performed these, you know how difficult they can be. Combining them with eccentric isometrics under eyes-closed conditions, though, makes them one of the most challenging, yet effective training techniques you can do for enhancing body kinematics, motor control, proprioception, and muscle function.
Note: Eccentric isometrics involve performing the negative phase of a lift in a controlled manner and holding the stretched position for a given duration. See video for a demo.
Double Offset Overhead Press
This one sounds complicated but it's simple in practice. There are two forms of offset loading involved – one is the actual load being heavier on one side, and the second is the use of a different training apparatus in each hand.
While one arm is performing a relatively standard overload movement in the form of a heavy dumbbell press, the other arm is performing a lighter, yet highly unstable pressing variation in the form of a bottoms-up press. The goal is to transfer the same crisp and proper mechanics produced from the bottoms-up technique to the arm that's simultaneously pressing the heavier dumbbell on the opposite side.
Once mastered, the movement should appear seamless and synchronized as if you were using the same tools and loads on each side with no visible differences in body position and mechanics. This requires a high degree of neuromuscular coordination, body awareness, sensory integrated movement, and mental focus.
Hanging Band Press
The hanging band technique (HBT) is a great variation for reinforcing proper technique, motor control, stability, symmetrical loading, and coordination.
The instability of the barbell does wonders for waking up proprioceptive mechanisms, as muscle spindles and other sensory receptors must work overtime to continually adjust to the erratic movements. It's particularly challenging on the overhead press due to the heightened center of mass and lack of support. Every muscle in your body must work overtime to lock the movement in.
This technique can be applied to standard Olympic barbells or specialty bars such as bamboo bars, which are designed specifically to magnify the oscillations.
Draping Chain Overhead Press
The draping chain technique is similar to HBT training. The main difference is there's a greater emphasis on sway and barbell tilt rather than quick and rapid oscillations. If you tend to favor one side, lack symmetry, or use any compensation pattern, there will be significant tilt in the barbell as the chains begin to sway almost uncontrollably.
Isolateral Hanging Band Overhead Press
The hanging band technique can be applied isolaterally by simply looping the weight and bands through standard cable grips/handles. The resulting instability is enough to force any lifter to slow the movement down and focus on movement mechanics.