Purpose: This study analyzed the effects of 3 training interventions: 1 isolated endurance training (ET) and 2 concurrent training (CT), which differed in the velocity loss (VL) magnitude allowed during the resistance training (RT) set: 15% (VL15) versus 45%, on strength and endurance running performance. Methods: A total of 33 resistance- and endurance-trained men were randomly allocated into 3 groups: VL15, VL 45%, and ET. ET was similar across all groups. The CT groups differed in the VL allowed during the RT set. Before and after the 8-week training program the following tests were performed: (1) running sprints, (2) vertical jump, (3) progressive loading test in the squat exercise, and (4) incremental treadmill running test up to maximal oxygen uptake. Results: Significant differences (P < .001) in RT volume (approximately 401 vs 177 total repetitions for VL 45% and VL15, respectively) were observed. Significant “group” × “time” interactions were observed for vertical jump and all strength-related variables: the CT groups attained significantly greater gains than ET. Moreover, a significant “group” × “time” interaction (P = .03) was noted for velocity at maximal oxygen uptake. Although all groups showed increases in velocity at maximal oxygen uptake, the VL15 group achieved greater gains than the ET group. Conclusions: CT interventions experienced greater strength gains than the ET group. Although all groups improved their endurance performance, the VL15 intervention resulted in greater gains than the ET approach. Therefore, moderate VL thresholds in RT performed during CT could be a good strategy for concurrently maximizing strength and endurance development.
Miguel Sánchez-Moreno, David Rodríguez-Rosell, David Díaz-Cueli, Fernando Pareja-Blanco, and Juan José González-Badillo
Pedro Jiménez-Reyes, Fernando Pareja-Blanco, David Rodríguez-Rosell, Mario C. Marques, and Juan José González-Badillo
To determine what variables determine the differences in performance on 2 tests of squat jump (SJ) performed under light load in highly trained athletes using maximal velocity (Vmax) or flight time (FT) as the discriminating factor of SJ performance.
Thirty-two participants performed 2 maximal weighted SJs using a force platform synchronized with a linear transducer. Mean force (Fmean), mean and maximal power (Pmean, Pmax), peak force (PF), maximal rate of force development (RFDmax), and time required to attain PF (TPF) and RFDmax (TRFDmax) were analyzed. SJs were divided into 2 segments: from the initiation of force application to PF1 and from the moment after PF1 to Vmax.
Traditional significance statistics revealed significant differences in the same variables between best and worst SJs using both FT and Vmax. However, to use an approach based on the magnitude of the effect, the best SJ showed greater Pmax (83/17/0%), Pmean (85/15/0%), Fmean (71/29/0%), RFDmax1 (73/27/0%), and PF1 (53/47/0%) and lower TPF2 (0/61/39%) than the worst SJ when Vmax was used to discriminate SJ performance. However, using FT to differentiate SJ performance, no difference was observed between best and worst.
Although jump height assessed through FT is a valid measure, these results suggest that Vmax is a more sensitive variable than FT to detect differences in loaded-SJ performance.
Luis A. Marco-Contreras, Beatriz Bachero-Mena, David Rodríguez-Rosell, and Juan J. González-Badillo
Purpose: To analyze the relationships between the evolution of training-load values and countermovement jump (CMJ) as an indicator of stress and fatigue in a high-level 800-m runner during a whole season, including indoor (ID) and outdoor season (OD). Methods: Over 42 weeks, daily training load was quantified as the result of the product of the intensity and volume, and it was termed load index (LI). CMJ was measured in every running session after warm-up and immediately after the last effort of the session. Other jump-related variables such as CMJ height loss, average weekly CMJ, initial CMJ of the next consecutive session, and initial CMJ of the following week were studied. Results: A significant negative relationship was observed between LI and weekly CMJ (ID: r = −.68, P < .001, common variance [CV] = 46%; OD: r = −.73, P < .001, CV = 53%), initial CMJ of the following week (OD: r = −.71, P < .01, CV = 50%), and CMJ height loss (ID: r = −.58, P < .01, CV = 34%; OD: r = −.52, P < .01, CV = 27%). A significant positive relationship was observed between LI and initial CMJ of the next consecutive session when LI values were <8 (OD: r = .72; P < .01, CV = 52%). However, from values ≥8, the relationship turned into a significant negative one (ID: r = −.74; P < .01, CV = 55%; OD: r = −64, P < .01, CV = 41%). Conclusions: CMJ may be a valid indicator of the degree of stress or fatigue generated by specific training sessions of a competitive athlete within a single session, a week, or even the following week. There could be an individual limit LI value from which the training volume does not allow a positive effect on high-speed actions such as a CMJ in the next consecutive session.
Miguel Sánchez-Moreno, David Rodríguez-Rosell, Fernando Pareja-Blanco, Ricardo Mora-Custodio, and Juan José González-Badillo
Purpose: To analyze the relationship between movement velocity and relative load (%1RM) in the pull-up exercise (PU) and to determine the pattern of repetition-velocity loss during a single set to failure in pulling one’s own body mass. Methods: Fifty-two men (age = 26.5 ± 3.9 y, body mass = 74.3 ± 7.2 kg) performed a first evaluation (T1) consisting of an 1-repetition-maximum test (1RM) and a test of maximum number of repetitions to failure pulling one’s own body mass (MNR) in the PU exercise. Thirty-nine subjects performed both tests on a second occasion (T2) following 12 wk of training. Results: The authors observed a strong relationship between mean propulsive velocity (MPV) and %1RM (r = −.96). Mean velocity attained with 1RM load (V1RM) was 0.20 ± 0.05 m·s−1, and it influenced the MPV attained with each %1RM. Although 1RM increased by 3.4% from T1 to T2, the relationship between MPV and %1RM, and V1RM, remained stable. The authors also confirmed stability in the V1RM regardless of individual relative strength. The authors found a strong relationship between percentage of velocity loss and percentage of performed repetitions (R 2 = .88), which remained stable despite a 15% increase in MNR. Conclusions: Monitoring repetition velocity allows estimation of the %1RM used as soon as the first repetition with a given load is performed, and the number of repetitions remaining in reserve when a given percentage of velocity loss is achieved during a PU exercise set.
David Rodríguez-Rosell, Felipe Franco-Márquez, Fernando Pareja-Blanco, Ricardo Mora-Custodio, Juan M. Yáñez-García, José M. González-Suárez, and Juan J. González-Badillo
To analyze the effects of low-load, high-velocity resistance training (RT) combined with plyometrics on physical performance in pre-peak-height-velocity (PHV) soccer players.
Thirty young soccer players from the same academy were randomly assigned to either a strength training (STG, n = 15) or a control group (CG, n = 15). Strength training consisted of full squat exercise with low load (45–58% 1RM) and low volume (4–8 repetitions/set) combined with jumps and sprints twice a week over 6 wk of preseason. The effect of the training protocol was assessed using sprint performance over 10 and 20 m, countermovement jump, estimated 1-repetition maximum, and average velocity attained against all loads common to pre- and posttests in full squat.
STG showed significant improvements (P = .004–.001) and moderate to very large standardized effects (ES = 0.71–2.10) in all variables measured, whereas no significant gains were found in CG (ES = –0.29 to 0.06). Moreover, significant test × group interactions (P < .003–.001) and greater between-groups ESs (0.90–1.97) were found for all variables in favor of STG compared with CG.
Only 6 wk of preseason low-volume and low-load RT combined with plyometrics can lead to relevant improvements in strength, jump, and sprint performance. Thus, the combination of field soccer training and lightweight strength training could be used for a greater development of the tasks critical to soccer performance in pre-PHV soccer players.
Fernando Pareja-Blanco, Eduardo Sáez de Villarreal, Beatriz Bachero-Mena, Ricardo Mora-Custodio, José Antonio Asián-Clemente, Irineu Loturco, and David Rodríguez-Rosell
Purpose: This study aimed to compare the effects of unresisted versus heavy sled sprint training (0% vs 40% body mass [BM]) on sprint performance in women. Moreover, the effects of the aforementioned loads on resisted sprint and jump performance were analyzed. Methods: Twenty-eight physically active women were randomly allocated into 2 groups: unloaded sprint training group (G0%, n = 14), and resisted sprint training with 40% BM group (G40%, n = 14). Pretraining and posttraining assessments included countermovement jump, unloaded 30-m sprint, and 20-m sprint with 20%, 40%, 60%, and 80% BM. Times to cover 0 to 10 (T10), 0 to 20 (T20), 0 to 30 (T30), 10 to 20 (T10–20), 20 to 30 (T20–30), and 10 to 30 m (T10–30) were recorded. Both groups were trained once a week for 8 weeks and completed the same training program, but with different loads (0% vs 40% BM). Results: No significant time × group interactions were observed. For unloaded sprint performance, G0% showed significant (P = .027) decreases only in T10–20, while G40% attained significant decreases in T30 (P = .021), T10–30 (P = .015), and T20–30 (P = .003). Regarding resisted sprint performance, G0% showed significant (P = .010) improvements only for the 20% BM condition. The G40% group attained significant improvements in all loading conditions (20%, 40%, 60%, and 80% BM). Both groups showed significant improvements (P < .001) in countermovement jump height. Conclusions: In physically active women, no significant differences in sprint and countermovement jump performance were detected after 8 weeks of resisted and unresisted sprint training programs. Future studies should, therefore, be devoted to how sprint training should be individualized to maximize performance.