|Single-arm dumbbell curls are unquestionably the exercise people will do most frequently with accentuated eccentrics and supra-maximal loads. Unfortunately, the study at hand used only leg exercises. So no information about arm-development, here..|
One of the classic methods to do just that is to utilize accentuated eccentric loading, i.e. to apply a greater external load during the eccentric phase of the lift as compared to the concentric phase (e.g. doing concentration curls with a supra-maximal weight, using the free arm to lift the weight up and only the working arm to slowly lower it, afterwards).In the twin-control group design study, Walker et al. conducted with thirty-three healthy young men had the subjects with 2-7 years of training experience either...
- switched to an accentuated eccentric load-training (AEL),
- continued on the classic split-training routine they were doing, anyway (CON), or
- followed a traditional concentric-eccentric isoinertial training program (TRAD).
TRAD and AEL engaged in two 5-week training periods where training was performed twice a week (Monday and Thursday or Tuesday and Friday, to allow at least 48 h recovery between training sessions). Training consisted of three sets of 6-RM (session 1) and 10-RM (session 2) bilateral leg press and unilateral knee extension and flexion exercises. [...] TRAD performed the exercises with the same load for both concentric and eccentric phases, while AEL performed the exercises with 40% greater load during the eccentric phase compared to the concentric phase (i.e. eccentric load = concentric load + 40%) [...] In order for each training session to include a true RM, both TRAD and AEL used loads that elicited concentric failure in at least 1 out of 3 sets with the investigator assisting the subject to complete the set.
|Figure 2: Illustration of how weight-releasers were used to add add. load on eccentrics (Walker. 2016).|
Custom weight-releasers were used to add the additional eccentric load to the leg press exercise (Figure 1, left) while weight plates were manually added and removed by the training supervisor(s) with the use of a custom-built pin for the knee extension exercise (Figure 1, right). Both groups performed the concentric and eccentric phases of the lift with a 2:2 s tempo (i.e. 4 s in total), which was monitored by the investigator" (Walker. 2016).Immediately after each training session TRAD and AEL subjects were given a standardized recovery drink containing 23 g of whey protein (8.47 g leucine and 5.08 g isoleucine per 100 g), 3 g of carbohydrate and 1.6 g of fat (Total+, Vital Strength, PowerFoods International Pty Ltd, Marrickville, New South Wales, Australia) to maximize the initial protein synthesis response to training and standardize post-exercise nutrition between groups.
|Figure 2: Overview of changes in performance markers (absolute, left; rel. right | Walker. 2016).|
|Figure 3: Changes in volunatary activation level (%) in the three study groups (Walker. 2016).|
- Walker, Simon, et al. "Greater strength gains after training with accentuated eccentric than traditional isoinertial loading loads in already strength-trained men." Frontiers in Physiology 7 (2016): 149.