Weights: Pumping vs Static Holds
So, let's say I can lift 25 pound barbells 8-10 times (the usual suggested) in, say, 30 seconds and then rest and repeat.
How will this develop muscle strength (and endurance?) differently than, say, holding the same 25 pound (or 20, if that's what it takes) for 30 seconds at (for example) 90 degrees from my body?
Or am I talking about two wildly different things?
Moving the weight would involve mainly concentric and eccentric (shortening and lengthening) contractions and just holding the weight would be an isometric contraction. It would be like comparing crunches and planks... they both have their own advantages in my opinion, but I couldn't tell you which one is better.