I've been racking my brain to come up with some effective eccentric-less exercises. I don't have the means to afford a sled or access to anything similar.
The idea of lifting with one lowering with 2 arms/limbs seems to sort of defeat the purpose as although the load on the eccentric portion is halved, its still of significance. I train alone so manuals are not an option.
I have tried one arm cable bench presses, catching the weight with my non-working arm and rotating at the hips to return the weight. I have access to a machine bench with a leg push bar that does effectively allow for one arm presses, catching the weight with the legs after lockout, then returning via all leg strength as you can take your hand off the bar. But these are pretty cumbersome, and are limited to really just pressing muscles. I've thought of doing push-ups with the feet elevated, starting from the floor, then after lockout, lower knees to the floor reset from the low chest-on-ground position. Again, though its just sort of awkward and the question of an efficient working load arises.
I then thought what about static holds? One leg/arm or both could be used - a load sufficient enough could certainly be used. CT answered a question about boxing as eccentric-less options, saying that it was not good not only b/c of the eccentric rebound but b/c of load. Well with statics, a sufficient load could be used and no eccentric lowering or rebound would be involved.
I do believe that actual shortening action of the muscle alone as in a concentric contraction is much more effective for enhancing nutrient uptake (upregulation of GLUT4 in the muscle cell membrain for enhanced glucose being one) which would not be experienced to the same extend with static holds. But neither would the impairment of nutrient uptak and neurvous system draining effects that "negatives" induce. The concept of the perfect rep/max force and its impact on neural activation would also not be present with static holds as the muscle does not shorten and the force production is much lower. However, the point of eccentric-less work is recovery - not max fast-twitch fiber recruitment and force production - like the standard high-threshold concepts ramping workouts and max force ideas. Thus, one of the reasons why lighter weights and higher reps are done(8-20+) and encouraged with the prowler/sled work.
It seems like a decent alternative if one doesn't have access to sleds, etc. to allow for some actual muscle work of enough load, volume sans eccentric contractions. I don't believe the nutrient uptake, recovery enhancing effects - or muscle building effects for that matter - would be on par with pure concentric-only training. But I'm curious if is a worthwhile second tier solution.
Any ideas or comments would be appreciated.