The aims of this systematic review were to synthetize the current evidence about (i) the force-velocity (FV) profile parameters (maximal values of force [F₀], velocity (V₀), and power [P_max]) obtained from the Samozino’s method in different sports; (ii) the association of the FV profile parameters with sport performance outcomes; and (iii) the effects of specific training programmes on the FV profile parameters. PubMed, SportDiscus, Web of Science, and Medline databases were searched for articles published between October 2008 (conception of the Samozino’s method) and October 2020. Twenty-one studies (10 descriptive, 6 correlational, and 5 longitudinal) met the inclusion criteria. The main findings revealed greater F₀, P_max, and V₀ values and better jump/sprint performance for high-level athletes compared to their low-level counterparts. The vertical P_max showed the highest correlation with jump height. The horizontal F₀, P_max, and V₀ were nearly perfectly correlated with 5/10-m, 10/20-m and 30/40-m sprint times, respectively. Training programmes using heavy- or light-loads specifically enhanced F₀ and V₀, respectively. These results suggest that the FV profile parameters discriminate between athletes of different sport disciplines and levels of practice, present significant correlations with a number of sport performance outcomes, and can be modified after short-term training programmes.

Baena-Raya, A, Jiménez-Reyes, P, Romea, ES, Soriano-Maldonado, A, and Rodríguez-Pérez, MA. Gender-specific association of the sprint mechanical properties with change of direction performance in basketball. J Strength Cond Res 36(10): 2868–2874, 2022—We evaluated the gender-specific associations between the mechanical variables derived from the horizontal force-velocity (FV) profile (i.e., theoretical maximal force [F ₀], velocity [V ₀], maximal power output [P max], peak ratio of the effective horizontal component [RF _peak ], and the force application technique index [D _RF ]) and the change of direction (COD) performance for basketball players. Seventy-one players (23 women and 48 men) were assessed for the horizontal FV profile and COD using the modified 505 and V-cut tests. The FV profile parameters were significantly higher for the men than those for the women. The F ₀ , RF _peak , and P max were strongly associated with performance in the 505 test (women r _range = −0.72 to −0.82; men: r _range = −0.67 to −0.75; p < 0.001) and the V-cut test (women r _range = −0.68 to −0.76; men r _range = −0.45 to −0.50; p < 0.001), as well as with a lower COD deficit (women r _range = 0.58 to 0.75 (p < 0.01); men r _range = 0.49 to 0.54; all p < 0.001). For the women, a 1 N·kg⁻¹ increase of the F ₀ was associated with −0.20 seconds and −0.56 seconds in the 505 and V-cut tests, respectively, and 0.16 seconds for the COD deficit. In the men, it was associated with −0.13 seconds and −0.37 seconds in the 505 and V-cut tests, respectively, and 0.10 seconds for the COD deficit. F ₀ , RF _peak , and P max are the most determinant sprint mechanical properties to successfully COD and reduce the COD deficit. The horizontal FV profile assessment is recommended for diagnosing and prescribing a training program for basketball players.

This study aimed to describe the acceleration–speed (AS) profile of soccer players during competition and to analyse their seasonal changes and inter-player differences. The AS profile values (theoretical maximum acceleration (A₀) and speed (S₀)) of 14 elite soccer players were studied in 18 matches, which were divided into five season periods. The main findings showed the A₀ (6.20 ± 0.51 m/s²) and S₀ (9.18 ± 0.58 m/s) average team season values. Significant individual changes (p < 0.05 and effect size (Eta-squared, η²) > 0.5) were confirmed for A₀ (Players 4 and 8) and S₀ (Players 6, 8 and 11). Additionally, standard deviations (SD±) confirmed small (±0.20–0.60) to moderate (±0.60–1.20) seasonal variations for most players in A₀ (SD range: ±0.22 to ±0.69 m/s²) and S₀ (SD range: ±0.27 to ±0.90 m/s). SD showed small to moderate inter-player differences for each period for A₀ (SD range: ±0.39 to ±0.61 m/s²) and S₀ (SD range: ±0.53 to ±0.61 m/s). In summary, coaches are recommended to assess the AS profile to diagnose potential player seasonal changes in sprinting performance, especially for A₀, which seems to be more sensitive to variations than S₀.

Baena-Raya, A, Díez-Fernández, DM, López-Sagarra, A, Martínez-Rubio, C, Soriano-Maldonado, A, and Rodríguez-Pérez, MA. Novel curvilinear sprint test in basketball: reliability and comparison with linear sprint. J Strength Cond Res 37(9): e535–e540, 2023—This study (a) evaluated the reliability of a curvilinear sprint (CS) test to assess kinetic and kinematic outcomes in basketball players, (b) compared the kinetic and kinematic outcomes derived from curvilinear vs. linear sprints (LS), and (c) examined the association of both the CS and LS with change of direction (COD) performance. Thirty young basketball players (17 men and 13 women) competing at the national level (i.e., Spanish Basketball National League) performed a novel CS test around the 3-point line (the 3-point line CS test) to the right and left sides. The maximum and average values of acceleration (ACC), velocity (VEL), and centripetal force (CentF) were measured using Local Positioning System technology (WIMU PRO, Realtrack Systems S.L., Almería, Spain). All outcomes showed a high relative (intraclass correlations coefficient ≥ 0.90) and absolute (coefficient of variation [CV] < 5%) reliability, except the maximal CentF to the right (CV = 5.41%) and left sides (CV = 7.72%). Linear sprints displayed higher ACC and VEL outputs compared with the 3-point line CS test (all p < 0.001). Both sprinting tests were very large to nearly perfect associated with COD performance (LS r range from −0.71 to −0.86; CS r range from −0.68 to −0.94; p < 0.001), and the curvilinear ACC_max was the kinematic outcome most strongly associated with COD performance (r range from −0.73 to −0.94). In conclusion, the 3-point line CS test is reliable to measure CS performance in basketball and presents different kinetic and kinematic features than LS.

This study examined which mechanical variables derived from a vertical jump (i.e. concentric peak force [ConcPF] and eccentric peak force [EccPF], flight time [FT]: contraction time [CT], eccentric deceleration rate of force development [EccDecRFD]) and linear sprint (i.e. theoretical maximal force [F₀] and velocity [V₀], maximal power output [P_max], the peak ratio of the effective horizontal component [RF_peak], and the index of force application technique [DRF]) determined the change of direction (COD) performance to a greater extent. Sixteen male soccer players (age: 21.8 ± 2.9 years; height: 175.94 ± 6.88 cm; weight: 73.23 ± 9.59 kg) were assessed for a countermovement jump, the horizontal force velocity (FV) profile, and the COD ZigZag test. The horizontal FV profile parameters were significantly associated with COD performance, while jump mechanical variables did not show any significant association (r = 0.08–0.19; p > 0.05). Specifically, F₀ (r = −0.56), P_max (r = −0.68), and RF_peak (r = −0.54) were strongly associated with COD performance. Moreover, a 1 N·kg⁻¹ increase in F₀ was associated with −0.11 s to complete the ZigZag test, whereas 1 W·kg⁻¹ and 1% increase in P_max and RF_peak were associated with −0.05 and −0.03 s, respectively, to complete the COD test. Horizontal force production during sprinting might play a key role in COD performance. Assessing the horizontal FV profile might help coaches to prescribe a specific training programme to maximize sprint acceleration, which might improve COD performance.

Sprint running and change of direction (COD) present similar mechanical demands, involving an acceleration phase in which athletes need to produce and apply substantial horizontal external force. Assessing the mechanical properties underpinning individual sprint acceleration might add relevant information about COD performance in addition to that obtained through sprint time alone. The present technical report uses a case series of three athletes with nearly identical 20 m sprint times but with different mechanical properties and COD performances. This makes it possible to illustrate, for the first time, a potential rationale for why the sprint force-velocity (FV) profile (i.e., theoretical maximal force (F₀), velocity (V₀), maximal power output (P_max), ratio of effective horizontal component (RF_peak) and index of force application technique (D_RF)) provides key information about COD performance (i.e., further to that derived from simple sprint time), which can be used to individualize training. This technical report provides practitioners with a justification to assess the FV profile in addition to sprint time when the aim is to enhance sprint acceleration and COD performance; practical interpretations and advice on how training interventions could be individualized based on the athletes’ differential sprint mechanical properties are also specified.