Decline in Unintentional Lifting Velocity Is Both Load and Exercise Specific.

SAVE OFFLINE

Original Research

Decline in Unintentional Lifting Velocity Is Both Load and Exercise Specific Maddison Beck,1 William Varner,1 Lindsay LeVault,1 Johnathan Boring,2 and Christopher A. Fahs3 1

Department of Exercise Science, Lindenwood University Belleville, Belleville, Illinois; 2School of Health Sciences, Lindenwood University, St. Charles, Missouri; and 3College of Health Sciences, Logan University, Chesterfield, Missouri

Abstract Beck, M, Varner, W, LeVault, L, Boring, J, and Fahs, CA. Decline in unintentional lifting velocity is both load and exercise specific. J Strength Cond Res 34(10): 2709–2714, 2020—When monitoring the mean concentric velocity (MCV) for velocity-based resistance training, often a threshold in the decline in the MCV is used to regulate the number of repetitions performed. However, it is not clear if the decline in the MCV is affected by the type of exercise or the relative load used. Therefore, the purpose of this study was to compare the decline in the MCV between the overhead press (OHP) and deadlift (DL) during sets to fatigue at different loads. Thirty individuals (23 6 3 years) with current training experience with both the OHP and DL completed a 1 repetition maximum (1RM) protocol for the OHP and DL. Subjects then returned to the laboratory on 2 separate occasions and completed 1 set of the OHP and DL to volitional fatigue at either 70 or 90% of their 1RM in a randomized order. The open barbell system measured the MCV of all repetitions. The absolute and relative (%) decline in the MCV was calculated for each condition and compared between loads (70 vs. 90% 1RM) and between lifts (OHP vs. DL). An alpha level of 0.05 was used at the criterion for statistical significance. The absolute decline in the MCV was greatest for the 70% OHP condition (0.36 6 0.12 m·s21) followed by 90% OHP (0.19 6 0.10 m·s21), 70% DL (0.16 6 0.08 m·s21), and 90% DL (0.09 6 0.06 m·s21); all were significantly different from one another (p , 0.05) except for 70% DL vs. 90% OHP (p 5 0.441). There was a greater relative decline in the MCV for the OHP compared with the DL (50.1 6 11.8% vs. 28.5 6 11.8%; p , 0.001) and for 70% 1RM compared with 90% 1RM (44.5 6 12.0% vs. 34.1 6 12.0%; p , 0.001). These data suggest the decline in the MCV is both exercise and load specific. Applying a uniform velocity decline threshold for velocity-based training may reduce training volume to different extents depending on the exercise and relative load used. Key Words: mean concentric velocity, resistance training, velocity-based training, repetitions to fatigue

Introduction Traditionally, prescribing resistance training intensity has been based on a percentage of the 1 repetition maximum (1RM) or on the maximum load that can be lifted for a given number of repetitions (e.g., 5RM) (16). However, as movement velocity, usually the mean concentric velocity (MCV), is highly related to the relative load lifted (3,10,11), this has become a potential alternative to percentage-based loading. Using the MCV to prescribe training intensity, known as velocity-based training, does require additional time to set up and equipment compared with traditional percentage-based training (1) but may also be advantageous in providing objective feedback to the trainee providing an objective guide for adjusting training volume and load within a training session based on performance. Evidence suggests that velocitybased training may at least elicit similar strength and power adaptations as percentage-based training over a short-term period (6 weeks) despite a lower volume of exercise performed (4). One challenge introduced with velocity-based training is identifying the appropriate target MCV for use in training. Not only is the load-velocity profile exercise specific (6), but there is also a progressive decline in the MCV at a given load when performing repetitions to fatigue (12,14). To effectively use the MCV in adjusting training loads and volumes, a threshold for the decline in the MCV during a set of exercise needs to be defined. Address correspondence to Christopher A. Fahs, [email protected]. Journal of Strength and Conditioning Research 34(10)/2709–2714 ª 2020 National Strength and Conditioning Association

Evidence suggests that velocity-based training performed with greater decreases in the MCV (e.g., 40% velocity loss; i.e., close to muscular failure) produces greater hypertrophy than training performed with smaller decreases in the MCV (e.g., 20% velocity loss) (19). On the other hand, training with smaller decreases in the MCV (i.e., further from muscular failure) may elicit greater power adaptations (19,20). Velocity-based training studies have used various thresholds in the MCV decline to adjust training ranging from 15 to 40% decline in the MCV (4,19,20). One study which has used a defined decline in the MCV to adjust training volume has used a uniform threshold (20% decline in the MCV) for all exercises (4). However, the decline in the MCV during resistance exercise may be exercise specific as greater declines in lifting velocity occur during the squat compared with the bench press exercise when each exercise is performed to fatigue (14). If the decline in the MCV is to be used for velocity-based training, it is important to understand if the decline in the MCV is exercise specific because greater reductions in the MCV during training may be more favorable for hypertrophy (19) whereas smaller reductions in the MCV during training may be more beneficial for strength and power (20). If training to improve strength or power using a velocity stop that is too high for an exercise, or if training for hypertrophy and using velocity stop that is too low, the training stimulus could be less effective. Thus, to use velocity stops as effectively as possible, it is important to determine if the pattern of the MCV decline is different between exercises. To the best of our knowledge, no evidence exists on the pattern of the MCV decline with free weight exercise or with exercises such as the overhead press (OHP) or deadlift (DL).

2709

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.

Velocity Decline During Sets to Fatigue (2020) 34:10

Therefore, the primary purpose of this study was to compare the decline in the MCV between the OHP and DL during sets to fatigue at different loads. A secondary purpose of this study was to investigate if strength and relative local muscular endurance are related to the decline in the MCV during exercise performed to fatigue. We hypothesized that, based on the previous work (14), the decline in the MCV would be greater for the OHP compared with the DL and that the decline in the MCV would be greater for moderate load (70% 1RM) compared with high load (90% 1RM) exercise. In addition, we hypothesized that the decline in the MCV during fatiguing exercise would be related to relative strength and to relative local muscular endurance.

Methods Experimental Approach to the Problem Subjects visited the laboratory on 3 occasions. For each visit, subjects were instructed to avoid strenuous exercise for 24 hours before testing. Furthermore, testing dates for each subject were set to accommodate the subjects’ training schedule to ensure each subject felt physically ready to perform the testing with a maximal effort. Testing was rescheduled as needed to ensure each subject felt ready to provide a maximal effort. We did not control for the menstrual cycle in our subjects because this has been shown not to affect peak torque measurements in the lower body (13), and there are no data to suggest menstrual cycle influences the MCV. During the first visit each subject’s height and body mass was measured followed by 1RM testing for the OHP followed by 1RM testing for the DL. During visits 2 and 3, subjects performed a single set of the OHP to fatigue followed by a single set of the DL to fatigue using a load of either 70 or 90% of their 1RM in a randomized order. Each visit was separated by at least 48 hours. Subjects Thirty-two subjects (age range 18–32 years)participated in this study. All subjects were resistance trained and had experience with both the OHP and DL, which included a minimum of training with each lift once per week for at least 12 weeks within the last year. Two subjects dropped out after only completing the first visit (1RM testing) and 5 more dropped out after completing only 1 of the repetitions to fatigue testing visit leaving a final sample of 25 subjects, who completed all testing sessions. Table 1 presents the subject characteristics of both the 30 subjects who completed 1 loading condition and the 25 subjects who completed both loading conditions. All subjects who dropped out of the study did so because of scheduling difficulties. Lindenwood University-Belleville’s institutional review board approved this study, and all subjects were informed of the risks and benefits of the study before they provided written informed consent. Procedures Anthropometrics. Standing height was recorded to the nearest 0.01 m with a standard stadiometer (Tanita HR-200; Tanita Corporation, Arlington Heights, IL), and the body mass was recorded with a digital scale (Tanita BWB-800S Doctors Scale; Tanita Corporation) to the nearest 0.1 kg. The body mass index was calculated as body mass divided by height squared (kg·m22). One Repetition Maximum Testing. Subjects performed a standardized warm-up on a Monark cycle ergometer (Monark Ergomedic 828 E) at a self-selected light intensity (i.e., rating of

perceived exertion of 9–11) for 5 minutes. After this, subjects were given 5–10 minutes to perform self-selected warm-up activities (e.g., dynamic warm-ups, stretching, foam rolling, etc). One repetition maximum testing was completed for the OHP followed by the DL. For each exercise, subjects first completed 5–10 repetitions with a load of approximately 40% of their estimated 1RM followed by 3–5 repetitions with a load of approximately 67% of their estimated 1RM and then 2–3 repetitions with a load of approximately 80% of their estimated 1RM. After the warm-up, the load was then incrementally increased until the 1RM was determined within 5 attempts. The 1RM was recorded as the greatest load successfully lifted (kg). The relative 1RM was calculated as the 1RM divided by the subject’s body mass. A minimum of 2 minutes rest was allotted between the warm-up sets, and a minimum of 3 minutes rest was allotted between all 1RM attempts. For the OHP, the subject began standing fully erect with the barbell grasped in the hands at approximately the level of the clavicles. A successful repetition was completed when the subjects lifted the barbell overhead in a balanced position (i.e., barbell aligned vertically with the midfoot) with the elbows fully extended and the shoulders in flexion with the arms overhead. Subjects were not allowed to use their quadriceps (i.e., no knee flexion/extension) to initiate the OHP. For the DL, subjects were allowed to use their preferred stance (sumo style or conventional style) and grip (double overhand, over/under, or hook grip). The barbell began motionless on the ground. A successful repetition was completed when the subject lifted the barbell from the ground to a point in which the knees and hips were fully extended with the subject standing fully upright. No hitching or supporting the barbell on the thighs was permitted. Sets to Fatigue. During the second and third visit to the laboratory, each subject completed a single set to fatigue of the OHP followed by a single set to fatigue of the DL using either 70 or 90% of their 1RM in a randomized order. The same general warm-up that was used during the 1RM testing was used during this testing. For the 70% 1RM condition, subjects completed 8–12 repetitions with 35% of their 1RM followed by 4–8 repetitions at 55% of their 1RM before the set to fatigue. For the 90% 1RM condition, subjects completed 6–10 repetitions with 45% of their 1RM followed by 4–6 repetitions at 70% of their 1RM before the set to fatigue. A minimum of 2 minutes rest was allotted between the warm-up sets.

Table 1 Subject characteristics.*† N 5 30 Age (y) Men/women (n) Body mass (kg) Height (m) BMI (kg·m22) OHP 1RM (kg) DL 1RM (kg) OHP 1RM MCV (m·s21) DL 1RM MCV (m·s21) Relative OHP 1RM Relative DL 1RM OHP 70% reps to fatigue (n) DL 70% reps to fatigue (n) OHP 90% reps to fatigue (n) DL 90% reps to fatigue (n)

23 6 3 23/7 94.5 6 25.6 175.0 6 9.4 30.9 6 7.3 65.9 6 21.9 174.9 6 51.2 0.22 6 0.13 0.19 6 0.07 0.70 6 0.18 1.87 6 0.44 11 6 3 10 6 5 562 462

N 5 25 23 6 3 20/5 95.4 6 27.1 175.0 6 9.3 31.0 6 8.0 64.9 6 19.8 173.0 6 48.0 0.22 6 0.14 0.18 6 0.05 0.69 6 0.16 1.85 6 0.44 12 6 3 11 6 6 562 462

*BMI 5 body mass index; OHP 5 overhead press; DL 5 deadlift; MCV 5 mean concentric velocity. †Data presented as mean 6 SD.

2710

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.

Velocity Decline During Sets to Fatigue (2020) 34:10

| www.nsca.com

Subjects used the same technique during the sets to fatigue as they did during 1RM testing. The same criteria that were used to determine a successful repetition during the 1RM testing were used to determine the number of successful repetitions completed during the sets to fatigue. Subjects were instructed to perform as many repetitions as possible with maximum effort given during each repetition, and strong verbal encouragement was provided during the sets. The number of consecutive successful repetitions was recorded for each condition. Mean Concentric Velocity. The Open Barbell System (Squats & Science Labs LLC, Seattle, WA) was attached to the barbell during the 1RM testing and sets to fatigue which recorded the MCV of each repetition. This device provides a valid measurement of the MCV compared with a 3D motion capture system (9). For the OHP, the unit was placed on a box under the barbell with the cable attached to the end of the barbell just inside the sleeve such that the cable was vertically aligned with the motion of the barbell during each repetition. For the DL, the unit was placed on the floor in the center of the barbell such that the cable was vertically aligned with the motion of the barbell during each repetition. For both exercises (OHP and DL) and for both loads (70 and 90%), the highest and lowest MCV value during each condition was recorded. The absolute decline in the MCV was calculated as the difference between the highest and lowest MCV value recorded during each condition. The relative decline in the MCV was calculated as the absolute decline in the MCV as a percentage of the highest MCV value recorded during each condition. The average MCV was calculated as the mean MCV value across all repetitions in each condition. The reliability of the decline in the MCV during sets to fatigue is high, with coefficients of variation of 2.1–6.6% (12). Statistical Analyses The data were reviewed for outliers, and assumptions of normality and homogeneity were met for all statistical tests. Independent samples t tests were used to test for differences in MCV values between subjects who chose to perform the DL sumo style (n 5 6) and those who chose to perform the DL conventional style (n 5 24). A 2 3 2 (lift 3 load) analysis of variance (ANOVA) with repeated measures was used to analyze the absolute and relative decline in the MCV as well as the highest, lowest, and average MCV values. When a significant interaction was observed, paired samples t tests were used to determine difference between conditions. Paired samples t tests were also used to determine significant differences in MCV values between individual repetitions within each condition. Pearson’s product-moment correlations were used to evaluate the relationships between the number of repetitions performed, relative strength, and the highest, lowest, average MCV, and the absolute and relative decline in the MCV. Data are presented as mean 6 SD. An alpha level of 0.05 was used at the criterion for statistical significance. Statistical analyses were performed using JASP version 0.11 (Amsterdam, the Netherlands). It was determined that a sample size of 24 (N 5 24) would be adequate to detect a significant main effect (lift or load) assuming an effect size of 0.25 (14), an alpha level of 0.05, and a beta of 0.80 (G*Power software, version 3.1.9.4).

Results There were no differences (p . 0.05) in MCV values between subjects who performed the DL sumo style (n 5 6) compared with those who performed the DL conventional style (n 5 24).

The 2 3 2 ANOVA revealed a significant interaction effect (lift 3 load) in the absolute decline in the MCV (p 5 0.003; F 5 11.060, h2 5 0.034). The absolute decline in the MCV was greatest for the 70% OHP condition (0.36 6 0.12 m·s21) followed by 90% OHP (0.19 6 0.10 m·s21), 70% DL (0.16 6 0.08 m·s21), and 90% DL (0.09 6 0.06 m·s21); all were significantly different from one another (p , 0.05) except for 70% DL vs. 90% OHP (p 5 0.441) (Figure 1A). There was a significant main effect for both load (p , 0.001; F 5 14.755, h2 5 0.077) and lift (p , 0.001; F 5 69.755, h2 5 0.332) but no interaction effect (p 5 0.061; F 5 3.883, h2 5 0.015) in the relative decline in the MCV. There was a greater relative decline in the MCV for the OHP compared with the DL (50.1 6 11.8% vs. 28.5 6 11.8%; p , 0.001) and for 70% 1RM compared with 90% 1RM (44.5 6 12.0% vs. 34.1 6 12.0%; p , 0.001) (Figure 1B). There was a significant main effect for both lift (p , 0.001; F 5 30.946, h2 5 0.166) and load (p , 0.001; F 5 115.421, h2 5 0.378) but no interaction effect (p 5 0.528; F 5 0.412, h2 5 0.001) for the highest MCV. The highest MCV values for the OHP were greater than for the DL (0.52 6 0.09 vs. 0.41 6 0.09 m·s21; p , 0.001) and greater at 70% 1RM than at 90% 1RM (0.55 6 0.08 vs. 0.37 6 0.08 m·s21; p , 0.001) (Figure 1C). There was a significant interaction effect (p 5 0.001; F 5 13.840, h2 5 0.060) for the lowest MCV. The lowest MCV value during the 70% DL (0.33 6 0.08 m·s21) was greater (p , 0.001) than during the 90% DL (0.23 6 0.04 m·s21), 70% OHP (0.26 6 0.08 m·s21), and 90% OHP (0.24 6 0.06 m·s21). There were no other significant (p . 0.05) differences in the lowest MCV values between conditions (Figure 1D). There was a significant main effect for both load (p , 0.001; F 5 109.081, h2 5 0.437) and lift (p 5 0.012; F 5 7.582, h2 5 0.047) but no interaction effect (p 5 0.639; F 5 0.226, h2 5 0.001) for the average MCV. The average MCV values for the OHP were greater than for the DL (0.40 6 0.07 vs. 0.36 6 0.07 m·s21; p 5 0.012) and greater at 70% 1RM than at 90% 1RM (0.45 6 0.06 vs. 0.31 6 0.06 m·s21; p , 0.001) (Figure 1E). For the 70% OHP condition, the MCV was not significantly different (p . 0.05) between any of the first 3 repetitions but the MCV was the greatest for the third repetition (0.59 6 0.15 m·s21), and this was significantly (p , 0.05) greater than all subsequent repetitions. For the 70% OHP condition, a 20% decline in the MCV was observed at the eighth and all subsequent repetitions (Figure 2A). For the 90% OHP condition, the MCV was greatest for the first repetition (0.39 6 0.13 m·s21), which was significantly (p , 0.05) greater than the fourth and all subsequent repetitions. For the 90% OHP condition, a 20% decline in the MVC was observed at the fourth and all subsequent repetitions (Figure 2B). For the 70% DL condition, the MCV was greatest for the third repetition (0.49 6 0.08 m·s21), and this was significantly (p , 0.05) greater than the MCV during the first, fourth, sixth, and all subsequent repetitions; for this condition, a 20% decline in velocity was observed at repetition number 10 alone (Figure 2C). For the 90% DL condition, the MCV was greatest during the first repetition (0.39 6 0.13 m·s21), and this was significantly (p , 0.05) greater than the MCV during the second, fifth, and all subsequent repetitions; for this condition, a 20% decline in the MCV was observed for the fifth and all subsequent repetitions (Figure 2D). Relationships between the number of repetitions performed within each condition and MCV values are presented in Table 2. Generally, the number of repetitions performed was positively related to the decline in the MCV. Overhead press relative strength was significantly related (r 5 20.437; p 5 0.033) to the lowest MCV during the 90% OHP condition. No other

2711

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.

Velocity Decline During Sets to Fatigue (2020) 34:10

Figure 1. A–E) Mean concentric velocity values presented for each condition. ‡p , 0.05 interaction effect; †p , 0.05 main effect for load; *p , 0.05 main effect for lift; a, p , 0.05 vs. 70% OHP; b, p , 0.05 vs. 90% OHP; c, p , 0.05 vs. 70% DL; d, p , 0.05 vs. 90% DL. N 5 25. OHP 5 overhead press; DL 5 deadlift.

significant (p . 0.05) relationships between strength and MCV values were observed.

Discussion The purpose of this study was to compare the MCV decline between the OHP and DL during sets with fatigue at different loads. The main finding of this study is that the decline in the MCV is both exercise and load specific. The decline in the MCV during sets to fatigue is greater during the OHP compared with the DL and greater at 70% 1RM compared with 90% 1RM. Using a threshold of a 20% loss in the MCV as a velocity stop would result in a different number of repetitions performed for the OHP and DL at the same relative load. As the absolute decline in the MCV was different between exercises and loads, these data suggest that this difference was due in part to differences in both the highest and lowest MCV observed between conditions. Greater highest MCV values were observed for the OHP compared with the DL and for 70% 1RM compared with 90% 1RM. This is in agreement with the previous work

showing that the MCV varies according to load and that this loadvelocity profile is unique between the OHP and DL (6). Differences in the lowest MCV value between conditions also contributed to the difference in the decline in the MCV as the 70% DL condition had a greater lowest MCV value compared with all other conditions. This finding is unique as previous studies using the bench press (12) and squat (14) performed to fatigue at various loads have shown the final (i.e., lowest) MCV values to be similar between various loads. It is possible that this finding is a unique feature of the DL as the lowest MCV values were not different between loads (70 and 90%) for the OHP. Supporting this idea is the fact that subjects performed fewer average repetitions with the DL compared with the OHP a 70% 1RM which suggests that subjects may not have truly reached muscular failure with the DL at 70% 1RM, and thus, the lowest MCV value observed may have been greater than if true muscular failure were reached. Similar to this study, greater declines in the MCV have been shown during upper-body resistance exercise (bench press) compared with lower-body resistance exercise (squat) (14). The greater decline in the MCV during the OHP compared with the

2712

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.

Velocity Decline During Sets to Fatigue (2020) 34:10

| www.nsca.com

Figure 2. A–D, Mean concentric velocity values during each repetition of each condition. Error bars represent 95% confidence intervals. Significant differences between individual repetitions within each condition are noted in the text. N 5 30 for (A and B); N 5 25 for (C and D).

DL is likely because of a greater “highest” MCV achieved during the OHP. This is consistent with the work showing the OHP elicits greater MCV values compared with the DL at the same relative load (6). Also, similar to the bench press compared with the squat exercise (14), it is likely that the lower-body movement in this study (DL) involved a longer deceleration phase (and shorter acceleration phase) during the concentric portion of each repetition compared with the upper-body movement in this study (OHP). However, in contrast to the previous work (14), we also observed that the decline in the MCV was also affected by the exercise load. The use of a higher load (90% 1RM) and an overall greater range in loads (70–90% 1RM) in this study compared with the previous study (60–75% 1RM) (14) may explain this discrepancy. The use of this range of loads is a novel and important aspect of this study because these specific exercises and loads are likely to be used by those implementing velocity-based training and in fact have been used in velocity-based training programs (4). Because the decline in the MCV was shown to be affected by both exercise and load, applying a standard velocity stop of 20% would result in greater reductions in the number of repetitions performed for the OHP compared with the DL and also would cause a greater reduction in the volume performed at lower loads

Table 2 Relationships between the number of repetitions performed and MCV decline.* Absolute MCV decline Correlation coefficient p value Relative MCV decline Correlation coefficient p value

70% OHP

70% DL

90% OHP

90% DL

0.522 0.003

0.420 0.021

0.547 0.006

0.346 0.098

0.432 0.017

0.527 0.003

0.575 0.003

0.299 0.166

*MCV 5 mean concentric velocity; OHP 5 overhead press; DL 5 deadlift; N 5 25.

(70% 1RM) compared with higher loads (90% 1RM). Supporting this observation is a study which showed significantly lower volumes of exercise were performed for the back squat, bench press, and OHP but not the DL for velocity-based training compared with percentage-based training when using a velocity stop of 20% (4). This suggest that much like velocity ranges, velocity stops may need to be exercise specific to optimize the use of the MCV for velocity-based training. A secondary purpose of this study was to investigate if either relative strength (relative 1RM) or relative local muscle endurance (number of repetitions performed) was related to the decline in the MCV during each condition. Contrary to our hypothesis, relative strength was not related to the decline in the MCV. By contrast, relative local muscular endurance was positively related to the decline in the MCV for the OHP and for the DL at 70% 1RM. The fact that relative local muscular endurance is related to the decline in the MCV is supported by the previous work showing the decline in the MCV is greater as more repetitions are performed with a given load (12,14). We anticipated that relative strength would also be positively related to the decline in the MCV during each condition as relative strength has been shown to relate to lower MCV values at high loads (i.e., stronger individuals can “grind through” high loads) (6). Thus, based on these data it seem that only relative local muscular endurance influences the decline in the MCV. Future studies may wish to investigate other factors such as the muscle fiber type which may influence the decline in the MCV during resistance exercise. Our study is novel in the fact that we investigated the OHP and DL, whereas many previous investigations have focused on the squat (2,7,14,17,23,24) or bench press (8,12,14,18,21,22) exercises when studying the MCV. In addition, the use of free-weight exercises as opposed to the Smith machine increases the applicability to those using velocity-based training with free-weight exercises. It is possible that day-to-day fluctuations in performance affected the number of repetitions performed and MCV values by the subjects in our study. However, the use of

2713

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.

Velocity Decline During Sets to Fatigue (2020) 34:10

randomized, cross-over design in this study minimizes this influence. The biomechanics (5) and the MCV at a given load (15) may differ between the sumo-style and conventional-style DL. The inclusion of both sumo-style and conventional-style DLs in our study may have influenced our results; however, differences in the decline in the MCV between the OHP and DL were large and observed whether or not we excluded those subjects who used the sumo-style DL. Therefore, an advantage of including both styles of DL in our study is that the results may be generalizable to those who use either the sumo-style or conventional-style DL.

Practical Applications The results of this study highlight that both the type of exercise performed and the relative load used can influence the decline in the MCV. Trainers and trainees implementing percentage stops (e.g., 20% loss in MCV during a set) to regulate training volume with velocity-based training should be aware that a standard or uniform percentage stop may reduce the volume more for some exercises (e.g., OHP) than others (e.g., DL) and for lower load (e.g., 70% 1RM) exercise compared with higher load (e.g., 90% 1RM) exercise. These findings suggest that if training for hypertrophy, using a higher percentage of the MCV loss to dictate the end of a set would be more appropriate for the OHP compared with the DL (e.g., 50 vs. 30% MCV decline) so as to allow a sufficient volume of exercise to accumulate for either exercise. On the other hand, if training for strength or power, a lower percentage of MCV loss for the DL compared with the OHP (e.g., 15 vs. 30% MCV decline) may be more appropriate to avoid excessive fatigue. Future studies should empirically investigate the effect of MCV loss on training outcomes with these exercises to maximize the benefit of using the MCV during training.

Acknowledgments The authors thank the subjects who participated in this study for their time and effort. The authors also thank Dr. Michael Zourdos for sharing the Open Barbell System device. The authors declare no conflicts of interest. The results of this study do not constitute endorsement of the product by the authors or the National Strength and Conditioning Association.

References 1. Banyard HG, Tufano JJ, Delgado J, Thompson SW, Nosaka K. Comparison of the effects of velocity-based training methods and traditional 1RM-percent-based training prescription on acute kinetic and kinematic variables. Int J Sports Physiol Perform 14: 246–255, 2019. 2. Carroll KM, Sato K, Bazyler CD, Triplett NT, Stone MH. Increases in variation of barbell kinematics are observed with increasing intensity in a graded back squat test. Sports 5: 1–7, 2017. 3. Conceicao F, Fernandes J, Lewis M, et al. Movement velocity as a measure of exercise intensity in three lower limb exercises. J Sports Sci 34: 1099–1106, 2016.

4. Dorrell HF, Smith MF, Gee TI. Comparison of velocity-based and traditional percentage-based loading methods on maximal strength and power adaptations. J Strength Cond Res 34: 46–53, 2019. 5. Escamilla RF, Francisco AC, Fleisig GS, et al. A three-dimensional biomechanical analysis of sumo and conventional style deadlifts. Med Sci Sports Exerc 32: 1265–1275, 2000. 6. Fahs CA, Blumkaitis JC, Rossow LM. Factors related to average concentric velocity of four barbell exercises at various loads. J Strength Cond Res 33: 597–605, 2019. 7. Fahs CA, Rossow LM, Zourdos MC. An analysis of factors related to back squat concentric velocity. J Strength Cond Res 32: 2435–2441, 2018. 8. Garcia-Ramos A, Pestana-Melero FL, Perez-Castilla A, Rojas FJ, Gregory Haff GG. Mean velocity vs. Mean propulsive velocity vs. Peak velocity: Which variable determines bench press relative load with higher reliability? J Strength Cond Res 32: 1273–1279, 2018. 9. Goldsmith JA, Trepeck C, Halle JL, et al. Validity of the Open Barbell and Tendo Weightlifting Analyzer Systems versus the Optotrak Certus 3D motion capture system for barbell velocity. Int J Sports Physiol Perform 14: 540–543, 2018. 10. Gonzalez-Badillo JJ, Marques MC, Sanchez-Medina L. The importance of movement velocity as a measure to control resistance training intensity. J Hum Kinet 29A: 15–19, 2011. 11. Gonzalez-Badillo JJ, Sanchez-Medina L. Movement velocity as a measure of loading intensity in resistance training. Int J Sports Med 31: 347–352, 2010. 12. Gonzalez-Badillo JJ, Yanez-Garcia JM, Mora-Custodio R, RodriguezRosell D. Velocity loss as a variable for monitoring resistance exercise. Int J Sports Med 38: 217–225, 2017. 13. Gur H. Concentric and eccentric isokinetic measurements in knee muscles during the menstrual cycle: A special reference to reciprocal moment ratios. Arch Phys Med Rehabil 78: 501–505, 1997. ¨ 14. Izquierdo M, Gonzalez-Badillo JJ, Hakkinen K, et al. Effect of loading on unintentional lifting velocity declines during single sets of repetitions to failure during upper and lower extremity muscle actions. Int J Sports Med 27: 718–724, 2006. 15. Kasovic J, Martin B, Fahs CA. Kinematic differences between the front and back squat and conventional and sumo deadlift. J Strength Cond Res 33: 3213–3219, 2019. 16. Kraemer WJ, Ratamess NA. Fundamentals of resistance training: Progression and exercise prescription. Med Sci Sports Exerc 36: 674–688, 2004. 17. Loturco I, Pereira LA, Cal Abad CC, et al. Using bar velocity to predict the maximum dynamic strength in the half-squat exercise. Int J Sports Physiol Perform 11: 697–700, 2016. 18. McGrath GA, Flanagan EP, O’Donovan P, Collins DJ, Kenny IC. Velocity based training: Validity of monitoring devices to assess mean concentric velocity in the bench press exercise. J Aust Strength Cond 26: 23–30, 2018. 19. Pareja-Blanco F, Rodriguez-Rosell D, Sanchez-Medina L, et al. Effects of velocity loss during resistance training on athletic performance, strength gains and muscle adaptations. Scand J Med Sci Sports 27: 724–735, 2017. 20. Pareja-Blanco F, Sanchez-Medina L, Suarez-Arrones L, Gonzalez-Badillo JJ. Effects of velocity loss during resistance training on performance in professional soccer players. Int J Sports Physiol Perform 12: 512–519, 2017. 21. Perez-Castilla A, Piepoli A, Delgato-Carcia G, Garrido-Blanca G, GarciaRamos A. Reliability and concurrent validity of seven commercially available devices for the assessment of movement velocity at different intensities during the bench press. J Strength Cond Res 33: 1258–1265, 2019. 22. Sanchez-Medina L, Gonzalez-Badillo JJ, Perez CE, Pallares JG. Velocityand power-load relationships of the bench pull vs. bench press exercises. Int J Sports Med 35: 209–216, 2014. 23. Sanchez-Medina L, Pallares JG, Perez CE, Moran-Navarro R, GonzalezBadillo JJ. Estimation of relative load from bar velocity in the full back squat exercise. Sports Med Int Open 1: E80–E88, 2017. 24. Spitz RW, Gonzalez AM, Ghigiarelli JJ, Sell KM, Mangine GT. Loadvelocity relationships of the back vs. Front squat exercises in resistancetrained men. J Strength Cond Res 33: 301–306, 2019.

2714

Copyright © 2020 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.