Sixteen Weeks of Krav-Maga Training Improves Maximal Strength: Comparison Between Novice and Veteran Athletes

Aim: The study aimed to assess the strength development of individuals submitted to 16 weeks of specific Krav-Maga training.

Methods: 30 Krav-Maga practitioners participated in this study, divided into two groups according to the training status, novices in the modality (GN, n = 15) and veterans in the modality (GV, n = 15). In the 1st day the participants were submitted to anthropometric and body composition assessments to characterize the groups. Weight, height and fat percentage (%FAT) were measured using 7 skinfolds, according to Pollock protocol. On the second day, the maximum voluntary contraction (MVC) of individuals was measured in the following exercises: Shoulder press, back squat, and deadlift in this order. The subjects had 10 minutes to determine the highest load for each movement; After every 10 minutes there was a 3-minute interval for complete recovery. The specific training for the modality consisted of 16 weeks of Krav-Maga training, with the same pre-training evaluation protocols being performed in the 8th training week and post-training. The training was conducted and monitored by a qualified instructor with the required graduation for the modality. The Shapiro-Wilk test was used to determine the data normality. Data were expressed as mean and standard deviation for comparison between groups and different times. ANOVA was used for repeated measurements. In case of significant F values, the Holm-Sidák post-hoc was applied. The Effect Size was estimated by calculating the Partial Eta square (η²P), being classified as 0.01 - Trivial; 0.01 Small; 0.06 Medium; 0.14 Large. All statistics were performed on JASP software (version, 0.13.1, Amsterdam, Netherlands).

Results: The GN presented age of 36.7 ± 8.4 years; the height of 174 ± 0.1 cm, the weight of 78.0 ± 13.9 kilos, %FAT of 26.1 %; while the GV was aged 35 ± 12 years, the height of 1.73 ± 0.1 cm, the total weight of 79.6 ± 8.4 kg, %FAT of 24.1 ± 4.0 %. The strength development and comparison between groups are presented in figure 1.

Figure 1. Strength development during 18 weeks of Krav-Maga training. The white rectangle represents GN, Grey and black rectangle represents GV; * represents statistical differences between GN and GV; # represents statistical differences between training time (pre; 8°Wk; Post).

Conclusion: It is noted that both groups improved the total muscular strength in the three exercises with 18 weeks of Krav-Maga training, regardless of the training status, except for the back squat exercise, for which veterans showed a more significant improvement than novice subjects.