Module 4G Unstable Training: What NOT to Do

Unstable training was popular in the early 2000s and seems to be making a comeback.
The premise is that training on unstable surfaces feels difficult and thus must be beneficial.

Core Muscle Activation: Training on unstable surfaces doesn't always result in greater core muscle activation.
Compromised Force Generation: It almost always compromises force-generating capacity.
Athletic Performance: Generally does not translate into improvements in athletic performance.
Injury Rates: There's evidence that it may increase injury rates due to reduced capacity to generate force.

Compared muscle group activity during stable and unstable exercises.
Unstable core exercises (Swiss balls, planks) activated the longissimus far less than deadlifting, squatting, glute ham raises, isometric glute ham raises, or isometric hyperextensions.
Multifidus activation followed a similar pattern.
External obliques showed slightly more activation in push-ups with feet on a fitness orb, but nothing revolutionary compared to abdominal work.
Pelvic thrusts showed almost no activation.
Rectus abdominis might benefit, but regular loaded exercises like sit-ups, crunches, or steps on a glute ham raise device are comparable.

Examined EMG activation of vastus lateralis, biceps femoris, and erector spinae during isometric exercises on stable and unstable devices.
Unstable devices showed significantly less EMG activation for relative load comparisons.
Even at absolute load comparisons, the vastus lateralis had more activation at 59%, 67%, and 75%.
- Unstable devices do not enhance the ability to activate tissue as much as one might think.

Examined EMG activity of spinal stabilizers.
Found no significant increase in muscle activation in the spine stabilizers when exercising on a stability ball compared to a bench.
Using a stability ball in place of a traditional bench is not warranted as no increase in spinal stabilization muscular activation occurs.
The load that you can lift goes down.
- Load going down creates a scenario where you're not going to maximize force production.

Looked at Swiss ball exercises in a training study.
Found a significant increase in core stability but:
- No increase in muscle activation in the back and abdominal muscles.
- No improvements in running economy.
- No improvements in running posture.
Contrast: strength training on stable surfaces has been shown to improve both running economy and running posture.
Core stability training appears to be completely inefficient in improving endurance performance.

EMG activity was not enhanced in an isometric squat with unstable surface training.
Average EMG activation was higher in the stable environment.
Peak force and rate of force development are greater in a stable environment, which translates to better sports performance.

Compared stable vs. unstable training in soccer athletes over eleven weeks.
The unstable training group performed only one exercise each training session.
Stability training resulted in greater training adaptations than unstable training.
- Greater drop jump power output performance gain.
- Greater increase in countermovement vertical jump power.
- Greater increase in agility performance.
Conclusion: Training on unstable environments impedes performance increases seen with traditional strength training, even when only done as a supplemental exercise task.
It is highly recommended not to use unstable or perturbated training activities because it does not translate to performance gain and can negatively impact performance.

Bounce drop jump and countermovement jump performance:
- Unstable group: 0.8% gain
- Stable group: 3.2% gain
Countermovement jump predicted power went up by 2.4% with stable training.
Sprint times:
- 40-yard sprint (≈36.6 meters): 3.9% reduction (improvement) with stable training.
- 10-yard sprint: 7.6% reduction with stable training.
Supplemental training with an unstable device muted performance gain.
Agility:
- Stable training group had a 4.4% decrease (improvement).
Unstable training does not enhance performance and may actually negatively impact performance when compared to stable training.

Compared core strength training on stable vs. unstable surfaces.
Measured functional movement screens, countermovement jumps, 10-meter sprints, and repeated sprint ability pre- and post-training.
The unstable training group got slower in repeated sprint ability.
- Did not enhance training benefits for the athlete because repeated sprint ability is a beneficial training adaptation.

Unstable devices have a place in rehab because maximal capacity to produce load is compromised.
Rehab is not training; it prepares an athlete to train.
Once an athlete is no longer injured, then there is no need to use these types of exercises.

Avoid dangerous exercises:
- Juan Carlos Santana ruptured both ACLs demonstrating standing posture on a Swiss ball.
- Doing squats on suspended chains.
- Partial squats on DynaDiscs.
These activities compromise force production and create an unstable environment that can increase injury risk. They're not going to translate to performance for your athletes.

Mike Stone's advice: Don't do stupid stuff; focus on basic strength training and weightlifting methods.
- Weightlifting movements and large mass exercises through range of motion will help athletes improve performance.
Professor Stone has trained more athletes and professionals in the industry and has influenced the profession more than almost anyone.
- He is successful, and his research is convincing that all this stuff is not useful.
Gimmicks and strange exercises are useless.