I have about a month where I'll be working from home so I thought it would be a good time to give greasing the groove a try but there's a few things I'd like to ask about.
Neural and Technique Development
The Craig Marker article that nate posted provides some good information GTG.
GTG innervates and coordinates muscle fiber so that they learn to fire together at the same time. Doing so allows you to produce more force (Strength and Power, dependent on the training load percentage).
Neural and Technique is optimally developed with load that are...
1) Around 85% plus of a 1 Repetition Max with Traditional Strength Exercises; Squats, Bench Press, Deadlift, Pullups, etc.
Loads of 70% are effective to a degree in the development of Neural Training and Technique Development; but not as optimal as load that are closer to a 1 Repetition Max used with 85% plus.
That because the neural firing sequence and technique is different with load in the 70% vs the 85% range.
However, the lower training percentage does allow some carry over and minimizing muscle fatigue.
2) Power is achieved with...
a) 48 to 62% loading in Traditional Strength Training Movements.
b) 70 - 80% of 1 Repetition Olympic Lift (Power) Movements.
Can you gtg with pushups and pullups at the same time?
Yes
One of the benefits of alternating opposing muscle groups, it allows you to produce more force in each movement.
Is there a minimum or maximum number of sets recommended?
Sets
The number of Set is primarily determined by muscle fatigue.
Once muscle fatigue set in, the muscle firing sequence and technique are changed. That basically means you are performing a different exercise when you continue in a fatigued state.
The number or Repetition is kept low, 1-5 per set. Around 1 - 2 set is usually going to provide a greater training effect.
Would it be less effective to include slight variations, like change the hand position or include the occasional static hold?
Changing Hand Positions
Varying hand positions amounts to performing a different exercise. It's similar to going from a Flat Bench Press to an Incline Bench Press.
Varying exercises is one of the keys to increasing strength and increasing muscle mass.
However, it not effective for developing the neural firing sequence and technique in a specific movement.
In regular workouts, I assume I should minimize upper body pushing and pulling while doing this?
The Workout Batting Order
The key to GTG, Neural-Technique, Development is to...
1) Perform it first in your workout, when you are fresh.
2) As Marker's article basically stated, once muscle fatigue set in, Stop.
Continuing in a fatigued elicits a different training effect.
3) One you have performed you GTG training movements, you can move on to some other upper pushing and pulling movement.
As per Pet...
When I am tired with one of the two moves, I stop for the day for both of them.
As always, the danger with GTG is recovery, so here you have to be 'double careful'.