oik01

Feedback from this forum has been great and I have used it to adjust my position over time. It continues to be an evolving thing but the new issue I have noticed is that I tend to almost lean entirely on the front during very hard efforts. If I am at tempo or under threshold I feel like the weight balance is good for my position. But when doing intervals on trainer road, when I tire I tend to lean more and more as if I am just using all my energy to pedal and my core is no longer able to handle the weight. I assume this is a core strength issue and probably normal with intense efforts? No need to adjust my position for this? I have a significant saddle to handlebar drop and have considerable setback on my saddle because I find I like sitting a little backwards and having more weight on the saddle that way.

Eric F 

A whole lot depends on the type of effort. For a sprint, I'm going to be in the drops and out of the saddle, which puts a majority of the weight over the front wheel, but still enough on the rear wheel to keep traction. For a seated flat-ground(ish) effort, I'm most likely going to be on the hoods, with a low torso, and pretty balanced between the wheels. For a seated climbing effort, I might be on the tops, sitting more upright, with less weight on my hands, and weight more towards the rear wheel. However, sometimes I feel better climbing on the hoods, even for hard efforts.

Iride01 

So what's your issue?

Pain? Performance? Bike stability?

Carbonfiberboy 

Many people move onto the saddle nose during hard efforts. That would naturally move weight onto the bars. That's not a problem because one can't keep that up for long enough to tire the arms anyway. Whether one moves onto the nose or not largely depends on the muscle groups which the rider is accustomed to using. It's certainly not necessary, one just has to pedal a little differently during hard efforts.

OTOH if you are not moving your butt forward, just leaning more forward to put more weight over the downstroke pedal, then that downforce usually takes care of holding that torso weight up - that is if your back muscles are strong enough to transfer that pedal downforce to a torso upforce. So I guess that's your complaint. If so, yeah you need to strengthen your core.

The quickest way to do this is strength training, though just riding more intervals will take care of it in time. I'm using dumbbells because gyms are closed or at least I'm not going even if they were open. I do two things which are very effective:
1) One legged knee bends while holding dumbbells in each hand. I stand next to a wall or post so that the shoulder on the side of the exercising leg can brush it if necessary, to take care of possible balance issues. Go down and up quickly, bending the knee as far as you safely can, while holding the bent lazy leg behind you and leaning forward with the normal squat lean - or even a little more if you want. 3 sets of 10 with each leg.

2) Stiff-legged deadlifts with dumbbells. While keeping a very slight bend in the knees, lower a pair of dumbbells almost to the floor in front of you, then back up. 3 sets of 10. Don't do these fast. Lower slowly, pause briefly, than back up.

These two exercises target the exact muscles being used.

Trakhak

Simple: the harder you push on the pedals, the more you'll move your center of gravity forward. Compare the upright running position of marathoners to the forward lean of 100-yard-dash specialists.