Miras-Moreno, S, García-Ramos, A, Jukic, I, and Pérez-Castilla, A. Two-point method applied in field conditions: a feasible approach to assess the load-velocity relationship variables during the bench pull exercise. J Strength Cond Res 37(7): 1367–1374, 2023—This study explored the between-session reliability and concurrent validity of the load-velocity (L-V) relationship variables obtained from different methods during the Smith machine bench pull exercise. In a counterbalanced order, 23 resistance-trained male subjects performed 2 sessions against 6 different loads in one week and 2 sessions against the lightest and heaviest loads in another week. The L-V relationship variables (load-axis intercept [L ₀], velocity-axis intercept [v ₀], and area under the L-V relationship line [A _line]) were obtained using the mean and peak velocity by the standard multiple-point (all 6 loads were used for the L-V modeling), modified multiple-point (the data point that most reduced the coefficient of determination was omitted from the L-V modeling), and 2-point (only 2 loads were used for the L-V modeling) methods. The reliability of the L-V relationship variables was acceptable for all methods (within-subjects coefficient of variation [CV] = 2.09–9.21%). The standard multiple-point and 2-point methods provided greater reliability for all L-V relationship variables compared with the modified multiple-point method (CV_ratio ≥ 1.27), while the 2-point method provided similar (CV_ratio = 1.04 for A _line) or greater (CV_ratio = 1.50 for L ₀ and 1.62 for v ₀) reliability than the standard multiple-point method. The concurrent validity of the modified multiple-point and 2-point methods was acceptable for the L-V relationship variables (effect size ≤ 0.62; r ≥ 0.76). These results suggest that the 2-point method is not only a valid procedure but also more reliable, simpler, faster, and less prone to fatigue than multiple-point methods for assessing maximal neuromuscular capacities through the L-V relationship.

This study investigated the reliability and validity of linear sprint tests (LS) and curvilinear sprint tests (CS) using a GPS device (GPEXE lt). Twenty-one (21) student athletes completed a 40 m LS as well as a left and right CS. Maximum sprint speed (MSS) and split times at short (0–10 m), intermediate (0–20 m), and long (0–30 m) distances were determined using the GPEXE lt and single-beam timing gates (TG). Intrasession reliability and concurrent validity of GPEXE lt were assessed. The GPEXE lt consistently showed high reliability for MSS (ICC ≥ 0.95; CV ≤ 1.8%), despite underestimation compared to TG (bias = −2.57 to −0.95%; ICC ≥ 0.87). Acceptable reliability was observed for CS and LS intermediate and long distance split times (ICC ≥ 0.91; CV ≤ 2.1%), with lower reliability for short distances (ICC ≥ 0.70; CV ≤ 3.6%). The GPEXE lt split times for CS and LS showed good agreement with TG (ICC ≥ 0.66), but were overestimated at long distances (5.5–9.7%) and short distances (11.1–14.6%). Although the MSS was found to be the most reliable and valid variable to assess LS and CS speed performance with GPEXE lt, caution is needed due to limited validity.

This study compared the accuracy of the fastest mean velocity from set (MV_fastest) to predict the maximum number of repetitions to failure (RTF) between 2 variants of prone bench pull (PBP) exercise (Smith machine and free-weight) and 3 methods (generalized, individualized multiple-point, and individualized 2-point). Twenty-three resistance-trained males randomly performed 2 sessions during Smith machine PBP and 2 sessions during free-weight PBP in different weeks. The first weekly session determined the RTF-MV_fastest relationships and subjects completed single sets of repetitions to failure against 60-70-80-90%1RM. The second weekly session explored the accuracy of RTFs prediction under fatigue conditions and subjects completed 2 sets of 65%1RM and 2 sets of 85%1RM with 2 min of rest. The MV_fastest associated with RTFs from 1 to 15 were greater for Smith machine compared to free-weight PBP (F ≥ 42.9; P < 0.001) and for multiple-point compared to 2-point method (F ≥ 4.6; P ≤ 0.043). The errors when predicting RTFs did not differ between methods and PBP variants, whereas all RTF-MV_fastest relationships overestimated the RTF under fatigue conditions. These results suggest that RTF–MV_fastest relationships present similar accuracy during Smith machine and free-weight PBP exercises and it should be constructed under similar training conditions.

This study aimed to compare and associate the magnitude of the load–velocity relationship variables between the multiple-point and two-point methods and between the concentric-only and eccentric–concentric prone bench pull (PBP) variants. Twenty-three resistance-trained males completed a preliminary session to determine the concentric-only PBP one-repetition maximum (1 RM) and two experimental sessions that only differed in the PBP variant evaluated. In each experimental session they performed three repetitions against the 14 kg load (L1), two repetitions against the 85% 1 RM load (L4), three repetitions against an equidistant intermediate light load (L2), two repetitions against an equidistant intermediate heavy load (L3), and 1–5 1 RM attempts. The load–velocity relationship variables (i.e., load–axis intercept, velocity–axis intercept, and area under the load–velocity relationship line) were obtained from the multiple-point (L1-L2-L3-L4) and two-point (L1-L4) methods. All load–velocity relationship variables presented greater magnitudes when obtained by the two-point method compared with the multiple-point method (p < 0.001, ES_range = 0.17–0.43), while the load–velocity relationship variables were comparable between both PBP variants (p ≥ 0.148). In addition, the load–velocity relationship variables were highly correlated between both methods (r_range = 0.972–0.995) and PBP variants (r_range = 0.798–0.909). When assessing the load–velocity relationship variables, practitioners should prescribe only two loads, as this maximises the magnitudes of the variables and decreases fatigue.

The present study investigates the effect of an acute intake of caffeine on the diurnal variation of neuromuscular performance in resistance‐trained women. A total of 15 resistance‐trained women participated in the current triple‐blind, placebo‐controlled, crossover experimental study. We assessed neuromuscular performance (i.e. ballistic (countermovement jump [CMJ] height and bench press throw [BPT] peak velocity), maximal strength (squat and bench press [BP] one‐repetition maximum [1RM]), and strength‐endurance [average velocity of the set during squat and number of repetitions‐to‐failure in BP]) four times at within 7 days. The participants ingested an acute dose of caffeine (3 mg/kg) or a placebo at 9–11 am and/or 17–19 pm. CMJ height (P = .016) and BP peak velocity (P = .012) were higher in the afternoon than in the morning. Compared to placebo, caffeine intake increased CMJ height by 3.1% in the morning and 1.6% in the afternoon (P = .035), but it had no effect on BPT peak velocity (P = .381). Maximal strength and strength‐endurance performances were not affected by the time‐of‐day or caffeine intake (all P > .3). No significant interaction (time‐of‐day x substance) was observed in any of the above‐mentioned outcomes (all P > .1). In conclusion, an acute dose of caffeine in the morning was effective to restore CMJ performance to levels found in the afternoon, while this effect was not observed neither in BPTpeak velocity nor in lower‐ and upper‐body maximal strength and strength‐endurance performance. Moreover, lower‐ and upper‐body ballistic performance were greater in the afternoon than in the morning in resistance‐trained women, while the acute intake of caffeine was only effective to increase CMJ height.Highlights Ballistic performance is probably higher in the afternoon than in the morning in resistance‐trained women. An acute intake of caffeine is effective to increase countermovement jump performance. The ingestion of an acute dose of caffeine in the morning restored countermovement jump performance to levels found in the afternoon.

Purpose: To explore the association of the load–velocity (L-V) relationship variables and ability to maintain maximal mechanical performance during the prone bench-pull exercise with sprint swimming performance and in-water forces. Methods: Eleven competitive adult male swimmers (50-m front crawl World Aquatics points: 488 [66], performance level 4) performed 1 experimental session. The L-V relationship variables (L0 [ie, maximal theoretical load at 0 velocity]; v0 [ie, maximal theoretical velocity at 0 load], and Aline [ie, area under the L-V relationship]) and maximal mechanical maintenance capacity were assessed at the beginning of the session. Afterward, sprint swimming performance and in-water force production were tested through a 50-m front-crawl all-out trial and 15-s fully-tethered swimming, respectively. Results: Only v0 presented high positive associations with 50-m time and swimming kinematics (r > .532; P < .046). The L0, v0, and Aline showed very high positive associations with the in-water forces during tethered swimming (r > .523; P < .049). However, the ability to maintain maximal mechanical performance, assessed by the mean velocity decline during the prone bench pull, was only significantly correlated with stroke rate (r = −.647; P = .016) and stroke index (r = .614; P = .022). Conclusions: These findings indicate that maximal neuromuscular capacities, especially v0, have a stronger correlation with swimming performance and in-water force production than the ability to maintain maximal mechanical performance in level 4 swimmers.