The ability to produce force rapidly and to maintain it is essential to sports performance. Although rapid force production and endurance are indispensable characteristics of optimal health and performance, assessing these qualities of strength is difficult because of clinician time constraints. The purpose of this study was to determine if peak force is a predictor of rate of force production and strength endurance. The results indicated peak force is a predictor of rate of force development, but not strength endurance. Clinicians should assess both maximum strength and endurance to gain a more complete picture of lower extremity strength deficits.
Roger O. Kollock, Bonnie Van Lunen, Stacie I. Ringleb, and James Onate
Kris Beattie, Brian P. Carson, Mark Lyons, and Ian C. Kenny
Maximum- and reactive-strength qualities both have important roles in athletic movements and sporting performance. Very little research has investigated the relationship between maximum strength and reactive strength. The aim of this study was to investigate the relationship between maximum-strength (isometric midthigh-pull peak force [IMTP PF]) and reactive-strength (drop-jump reactive-strength index [DJ-RSI]) variables at 0.3-m, 0.4-m, 0.5-m, and 0.6-m box heights. A secondary aim was to investigate the between- and within-group differences in reactive-strength characteristics between relatively stronger athletes (n = 11) and weaker athletes (n = 11). Forty-five college athletes across various sports were recruited to participate in the study (age, 23.7 ± 4.0 y; mass, 87.5 ± 16.1 kg; height, 1.80 ± 0.08 m). Pearson correlation results showed that there was a moderate association (r = .302–.431) between maximum-strength variables (absolute, relative, and allometric scaled PF) and RSI at 0.3, 0.4, 0.5 and 0.6 m (P ≤ .05). In addition, 2-tailed independent-samples t tests showed that the RSIs for relatively stronger athletes (49.59 ± 2.57 N/kg) were significantly larger than those of weaker athletes (33.06 ± 2.76 N/kg) at 0.4 m (Cohen d = 1.02), 0.5 m (d = 1.21), and 0.6 m (d = 1.39) (P ≤ .05). Weaker athletes also demonstrated significant decrements in RSI as eccentric stretch loads increased at 0.3-m through 0.6-m box heights, whereas stronger athletes were able to maintain their reactive-strength ability. This research highlights that in specific sporting scenarios, when there are high eccentric stretch loads and fast stretch-shortening-cycle demands, athletes’ reactive-strength ability may be dictated by their relative maximal strength, specifically eccentric strength.
Irineu Loturco, Lucas A. Pereira, Tomás T. Freitas, Chris Bishop, Fernando Pareja-Blanco, and Michael R. McGuigan
Maximum strength (MS) is a basic capacity that underpins several physical and technical skills, being generally described as “the greatest force possible under specified conditions.” 1 , 2 MS is usually assessed by the 1-repetition maximum (1RM) test and has been shown to be closely related to a
Claire J. Brady, Andrew J. Harrison, Eamonn P. Flanagan, G. Gregory Haff, and Thomas M. Comyns
that can be examined. Peak force (PF, maximum force produced) is indicative of “maximum strength,” and rate of force development (RFD) is indicative of an athlete’s ability to produce maximal force in minimal time. 5 To describe different portions of the force–time curve, Zatsiorsky 6 calculated the
Irineu Loturco, Timothy Suchomel, Chris Bishop, Ronaldo Kobal, Lucas A. Pereira, and Michael McGuigan
, according to the objectives and needs of a given athlete or sport discipline. 1 , 2 For example, programs designed to develop maximum strength capacity tend to adopt loading ranges varying between 80% and 100% 1RM, whereas programs focused on developing muscle power normally prioritize the use of exercises
Amador García-Ramos, Guy Gregory Haff, Francisco Luis Pestaña-Melero, Alejandro Pérez-Castilla, Francisco Javier Rojas, Carlos Balsalobre-Fernández, and Slobodan Jaric
. Prediction of one repetition maximum strength from multiple repetition maximum testing and anthropometry . J Strength Cond Res . 2006 ; 20 : 584 – 592 . PubMed doi:10.1519/R-15304.1 16937972 12. Jovanonic M , Flanagan EP . Researched applications of velocity based strength training . J Aust Strength
Martha Walker, Donald Sussman, Michael Tamburello, Bonnie VanLunen, Elizabeth Dowling, and Beth Ernst Jamali
A strength-endurance diagram predicts that a person should be able to perform 30 repetitions of an exercise if the resistance level is 60% of 1-repetition maximum (1RM).
To compare the number of repetitions predicted by the diagram with recorded repetitions of a shoulder exercise.
Single-group comparison with a standard.
34 healthy adults (20 women, 14 men) with a mean age of 29 years (range 20–49).
Main Outcome Measures:
The number of repetitions that subjects could perform in good form of a shoulder exercise with resistance of 60% 1RM.
The mean number of repetitions was 21 (± 3, range 15–28), which was significantly different than the 30 repetitions that the diagram predicted.
The strength-endurance diagram did not accurately predict the number of repetitions of a shoulder exercise that subjects could perform.
Jessica A. Calderbank, Paul Comfort, and John J. McMahon
Purpose: The aim of the current study was to investigate the relationship between dive distance (DD) and countermovement jump (CMJ) height, track start CMJ height, countermovement broad jump (CMBJ) distance, track start broad jump distance, and isometric midthigh pull peak force and relative peak force. Methods: A total of 27 (11 female and 16 male) regional-national-international-standard swimmers (mean [SD]; age = 19.5 [5.5] y; mass = 69.3 [10.5] kg; height = 1.77 [0.09] m) performed 3 trials of a track start dive, CMJ, track start CMJ, CMBJ, track start broad jump, and isometric midthigh pull. Results: Data were separated into pooled (females and males combined), females, and males. Large to very large correlations were found between DD and all variables tested for pooled data (r = .554–.853, P < .001–.008), with DD-CMBJ displaying the highest correlation (r = .853, P < .001). CMBJ accounted for 70% of the variance in DD. Females demonstrated moderate nonsignificant correlations between DD isometric midthigh pull (r = .379, P < .125). Males demonstrated very large significant correlations between DD-CMJ (r = .761, P < .001). Conclusions: DD demonstrated strong correlations with jump performances and multijoint isometric force production in pooled data. Males showed stronger correlations than females due to being stronger and being able to perform the jumping/strength tasks to a higher standard. Enhanced jump performance and increased maximal force production may, therefore, enhance DD in swimmers.
Glyn Howatson, Raphael Brandon, and Angus M. Hunter
There is a great deal of research on the responses to resistance training; however, information on the responses to strength and power training conducted by elite strength and power athletes is sparse.
To establish the acute and 24-h neuromuscular and kinematic responses to Olympic-style barbell strength and power exercise in elite athletes.
Ten elite track and field athletes completed a series of 3 back-squat exercises each consisting of 4 × 5 repetitions. These were done as either strength or power sessions on separate days. Surface electromyography (sEMG), bar velocity, and knee angle were monitored throughout these exercises and maximal voluntary contraction (MVC), jump height, central activation ratio (CAR), and lactate were measured pre, post, and 24 h thereafter.
Repetition duration, impulse, and total work were greater (P < .01) during strength sessions, with mean power being greater (P < .01) after the power sessions. Lactate increased (P < .01) after strength but not power sessions. sEMG increased (P < .01) across sets for both sessions, with the strength session increasing at a faster rate (P < .01) and with greater activation (P < .01) by the end of the final set. MVC declined (P < .01) after the strength and not the power session, which remained suppressed (P < .05) 24 h later, whereas CAR and jump height remained unchanged.
A greater neuromuscular and metabolic demand after the strength and not power session is evident in elite athletes, which impaired maximal-force production for up to 24 h. This is an important consideration for planning concurrent athlete training.
Lasse Ishøi, Per Aagaard, Mathias F. Nielsen, Kasper B. Thornton, Kasper K. Krommes, Per Hölmich, and Kristian Thorborg
Purpose: To investigate the association between hamstring muscle peak torque and rapid force capacity (rate of torque development, RTD) vs sprint performance in elite youth football players. Methods: Thirty elite academy youth football players (16.75 [1.1] y, 176.9 [6.7] cm, 67.1 [6.9] kg) were included. Isometric peak torque (in Newton meters per kilogram) and early- (0–100 ms) and late- (0–200 ms) phase RTD (RTD100, RTD200) (in Newton meters per second per kilogram) of the hamstring muscles were obtained as independent predictor variables. Sprint performance was assessed during a 30-m-sprint trial. Mechanical sprint variables (maximal horizontal force production [F H0, in Newtons per kilogram], maximal theoretical velocity [V 0, in meters per second], maximal horizontal power output [Pmax, in watts per kilogram]) and sprint split times (0–5, 0–15, 0–30, and 15–30 m, in seconds) were derived as dependent variables. Subsequently, linear-regression analysis was conducted for each pair of dependent and independent variables. Results: Positive associations were observed between hamstring RTD100 and F H0 (r 2 = .241, P = .006) and Pmax (r 2 = .227, P = .008). Furthermore, negative associations were observed between hamstring RTD100 and 0- to 5-m (r 2 = .206, P = .012), 0- to 15-m (r 2 = .217, P = .009), and 0- to 30-m sprint time (r 2 = .169, P = .024). No other associations were observed. Conclusions: The present data indicate that early-phase (0–100 ms) rapid force capacity of the hamstring muscles plays an important role for acceleration capacity in elite youth football players. In contrast, no associations were observed between hamstring muscle function and maximal sprint velocity. This indicates that strength training focusing on improving early-phase hamstring rate of force development may contribute to enhance sprint acceleration performance in this athlete population.