Differences between adjusted vs. non-adjusted loads in velocity-based training: consequences for strength training control and programming

Abstract

Strength and conditioning specialists commonly deal with the quantification and selection the setting of protocols regarding resistance training intensities. Although the one repetition maximum (1RM) method has been widely used to prescribe exercise intensity, the velocity-based training (VBT) method may enable a more optimal tool for better monitoring and planning of resistance training (RT) programs. The aim of this study was to compare the effects of two RT programs only differing in the training load prescription strategy (adjusting or not daily via VBT) with loads from 50 to 80% 1RM on 1RM, countermovement (CMJ) and sprint. Twenty-four male students with previous experience in RT were randomly assigned to two groups: adjusted loads (AL) (n = 13) and non-adjusted loads (NAL) (n = 11) and carried out an 8-week (16 sessions) RT program. The performance assessment pre- and post-training program included estimated 1RM and full load-velocity profile in the squat exercise; countermovement jump (CMJ); and 20-m sprint (T20). Relative intensity (RI) and mean propulsive velocity attained during each training session (Vsession) was monitored. Subjects in the NAL group trained at a significantly faster Vsession than those in AL (p < 0.001) (0.88–0.91 vs. 0.67–0.68 m/s, with a ∼15% RM gap between groups for the last sessions), and did not achieve the maximum programmed intensity (80% RM). Significant differences were detected in sessions 3–4, showing differences between programmed and performed Vsession and lower RI and velocity loss (VL) for the NAL compared to the AL group (p < 0.05). Although both groups improved 1RM, CMJ and T20, NAL experienced greater and significant changes than AL (28.90 vs.12.70%, 16.10 vs. 7.90% and −1.99 vs. −0.95%, respectively). Load adjustment based on movement velocity is a useful way to control for highly individualised responses to training and improve the implementation of RT programs.

Velocity-Based Resistance Training on 1-RM, Jump and Sprint Performance: A Systematic Review of Clinical Trials

“…This study showed statistically significant effects in full and parallel squat, but not in half squat. These findings are consistent with the fact that most of the studies reviewed have found positive results in full squat after a VBRT program [ 22 , 29 , 30 , 38 , 39 , 40 , 53 , 55 , 60 , 62 , 65 , 66 , 67 ].…”

“…However, after evaluating the abstracts, full-texts, and analyzing the strict fulfillment of the other inclusion criteria, 236 articles were excluded. A total of 22 studies met the pre-established requirements [ 22 , 29 , 30 , 38 , 39 , 40 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ]. Considering that the present systematic review is reported according to the parameters established in the PRISMA guidelines, a flow chart of the literature search is shown in Figure 1 .…”

“…In fact, only one study did not find positive effects after a VBRT protocol with 30% of VL [ 38 ]. Moreover, the research by Jiménez-Reyes et al [ 67 ] showed that non-adjusted loads during a VBRT program resulted in greater changes in 1-RM than adjusting training loads although the improvements were probably due to the former group working at lower relative intensity (with lower VL). According to the authors, this might have generated lower fatigue levels and greater performance benefits.…”

“…Fifteen studies have investigated the effect of VBRT on running sprinting (10–30 m) with a total of 406 strength-trained subjects [ 22 , 29 , 30 , 38 , 39 , 40 , 52 , 55 , 57 , 59 , 60 , 63 , 64 , 66 , 67 ]. However, only eight studies [ 29 , 30 , 39 , 55 , 59 , 60 , 66 , 67 ] concluded that VBRT has positive or superior effects to other strategies, while the other studies did not report improvements with respect to the control group. Despite these findings, it should be noted that VBRT does not negatively affect the sprinting ability of athletes.…”

“…In addition, there was a tendency to show greater increases in sprint performance when less percentage of VL was used in each training set. This resulted in lower total volume than the other groups and, therefore, a lower level of accumulated fatigue [ 29 , 30 , 39 , 55 , 59 , 60 , 66 , 67 ]. Although some studies have reported no significant difference in sprinting ability when comparing two groups training with different VL [ 22 , 38 ], several studies suggest that lower %VL (10–15%) could be the most appropriate fatigue level to improve 20 m sprint performance [ 29 , 30 , 39 ].…”