Acute Effects of Partial Range of Motion Resistance Training and Increases in Blood Lactate Impact Accuracy of Penalty Kicks in Soccer Players

Abstract

The purpose of this investigation was to assess the acute effects of partial range of motion (pROM) exercises, on the accuracy of soccer penalty kicks on goal. This method limits the joint from moving through the complete length of a motion, creates an occlusion effect, and thus causes the type 1 muscle fibers to work anaerobically. Thirty-six soccer players, with 5-8 years of soccer playing experience, were pretested for accuracy then retested ( rtt = 0.92 ) and divided into random groups from the Associação Banco do Brasil Futebol Clube—Group A, Paraná Futebol Clube—Group P, and Coritiba Futebol Clube—Group C. Groups were composed of 12 people performing full range of motion (fROM) exercises or pROM exercises. Both groups performed 5 sets of back squats at 50% of body weight in sets of 40 seconds with metronome tempo of 56 bpm for an average of 10-12 repetitions per 40-second set. Blood samples were collected post-warm-up, after the 3rd set, and following the 5th set for both groups, within 3–5 minutes of cessation of exercise. Athletes performing fROM exercises showed increased blood lactate from 2.69 ± 0.2 to 4.0 ± 1.2 mmol/L ( p < 0.05 ), and in pROM, blood lactate increased from 2.48 ± 0.42 to 10.29 ± 1.3 mmol/L ( p < 0.001 ). In fROM, accuracy decreased from 42.96 ± 13.39 % to 41.37 ± 17.25 % ( p > 0.1 ), a slight decrease, while in the pROM groups, accuracy decreased from 45.42 ± 14.93 % to 24.53 ± 10.2 % ( p < 0.001 ). The calculations demonstrating average percentages of accuracy are presented in the tables. These findings support that pROM exercises significantly increase blood lactate resulting in a reduction in soccer kick accuracy. This decrease in accuracy directly correlates to the accumulation of lactic acid and hydrogen ions (H+) and demonstrates that pROM strength training should not be utilized prior to a sport-specific session in order to avoid interference with the development of special skills.

Comparison of 10% vs. 30% Velocity Loss during Squat Training with Low Loads on Strength and Sport-Specific Performance in Young Soccer Players

“…In addition, the objective in soccer players would be to apply an RT stimulus that produces long-term benefits on physical performance without reducing acute performance during subsequent field soccer training. Previous studies have indicated that RT involving heavy loads and repetitions per set ending near or to muscle failure (i.e., high %VL in the set) induced greater immediate and short-term deteriorations in jump, sprint, and soccer skill performance compared to lower repetitions or %VL in the set [ 15 , 16 , 18 , 19 , 25 ]. Thus, RT programs with light loads and low %VL appear to be more efficient because they allow players to obtain the same or greater improvements but with a lower degree of fatigue and better performance in subsequent field soccer training.…”

“…Extensive literature has supported this approach as beneficial for maximizing strength gains and muscle hypertrophy [9,10]. However, RT with heavy loads and repetitions to failure presents some negative effects that limit its application in soccer players: (1) it tends to produce minimal gains or even detrimental effects on jump and sprint performance [7,8,[10][11][12]; (2) it is associated with a high degree of fatigue [13,14] and leads to decreased performance of technical-tactical actions (passing and shooting accuracy) during the subsequent specific field training [15,16]; and (3) this type of training does not guarantee the greatest gains in physical performance [10,12]. In contrast to the aforementioned approach, there are numerous studies showing that RT (combined or not with plyometric training) with moderate or low loads, low number of repetitions per set, and performing each repetition at maximal intended velocity, produces significant improvements in lower-limb strength, vertical jump, running acceleration, the ability to repeat sprints, and KB speed in soccer players of different ages and categories [1][2][3][4]12].…”