DCER (ISOTONIC) TRAINING IMPROVES STRENGTH AND ITS RETENTION IN TRAINED AND UNTRAINED LIMBS
Housh, T. J., Housh, D. J., Weir, J. P., & Weir, L. L. (1995). Effects of eccentric only resistance training and detraining. International Journal of Sports Medicine, 17, 145-148.
The effects on dynamic constant eccentric resistance (DCER - formerly called isotonic training) training on the extensor muscles of one leg were assessed for: eccentric DCER strength in both legs, concentric isokinetic leg extension peak torque-velocity curves in both legs, and retention of the previous two factors after detraining.
Males were divided into a training group (N = 9) and a non-training control group (N = 8). Training consisted of eight weeks of eccentric-only DCER exercise (3-5 sets of 6 repetitions at 80% of eccentric 1 RM) on the nondominant limb followed by an additional eight weeks of detraining.
DCER strength improved in the trained (29%) and untrained (17%) limbs. No changes in isokinetic values were recorded in either limb. The training increases were retained after eight weeks of detraining.
Implication. DCER (isotonic) training involves considerable neuromuscular skill development. It is known that initial strength training effects are neural (skill changes) and so it is not surprising that training "effects" are retained when development starts from an initially low level. This type of neural development also explains the "cross-training" effect to the untrained limb. Another explanation might be changes in everyday limb-use that stimulated development in the untrained limb.