Training spill over & background levels

In article <[email hidden]>, Chris Malcolm

Quoted message said:

I'm wondering about the best background exercise context while
training a set of muscles. There are two scenarios. The first is
during days of training sessions. Is it beneficial to raise the
general background level of activity of those muscles outside the
training sessions, e.g. by doing say an easy 10% or 20% of 1RM rep of
the training exercise now and then?

The second scenario is during a regular training holiday in which a
few non-training days are allowed for strain to subside and muscle
growth etc. to occur, e.g. taking weekends off. In this time is it
beneficial to perform occasional light (say 20% of 1RM) reps rather
than taking a complete rest? Is it also beneficial in this time to
exercise other muscle groups, e.g. legs when arms are taking a rest?
In other words, would there be a spill-over benefit to arm development
from doing leg training while the arms are in a recuperation training
holiday?

I've noticed the suggestion that there can be a symmetry spill-over in
training effect, e.g., training one arm will cause a slight benefit to
the other untrained arm. Is this a general spill-over from any trained
muscle set to another untrained set, or it specifically symmetrical?
If it's specifically symmetrical, it raises the interesting question
of whether it might be useful to train the two sides in different
interleaved regimes, so that one side, say one arm, was in
recuperation, while the other was being trained.

Trained muscles to another set? I dunno about that as I tend to think in
terms of athletic training, where you think in terms of movement instead
of muscles.

If you want to look at it another way - training qualities of speed,
strength and endurance in one movement invariably affects those qualities
both within that movement and in other movements. IOW - if I train
endurance I affect speed and strength. OTOH, if I train speed and strength
in a squat/jump type of movement the effect on a push/press type of
movement is less direct. (I'm deliberately avoiding using descriptions
such as 'hip extension/knee extension/plantar flexion' here, but hopefully
you'll get the idea)

As Elzi pointed out in another post training adaptations are multifactoral
and complex. You are affecting structure (protein synthesis -
hypertrophy), but you all also affecting neural factors, motor factors,
metabolic factors, etc.

So your idea of interleaved regimes is reductionist and completely ignores
multifactoral inputs to training. It can be done and it has been done. The
bodybuilding type of 'split' training is an example of this. But I would
question why you would want to do this when your goals are not muscle
mass.

Even for bodybuilders there is a recognition that systematic recuperation
is also necessary and their splits reflect this need.

If I were you I'd quit thinking in terms of 'muscle' and start thinking in
more athletic terms. As the old Russian coach once said, "If you vant to
press more, then press more." Frequency, intensity, volume and
restoration.