Changes in body composition due to weight reduction by elite youth judo athletes in short period pre-competition
Abstrakt
Background & Study Aim: The aim of the study was to present changes in body composition parameters due to pre-competitive body weight reduction, changes in directly measurable parameters of bio-impedance measurement (resistance, reactance, phase angle) and changes in total body water and its components, as well as the possibility to record changes in body composition if there is inconstant hydration, in elite Czech judo athletes using the bio-impedance method. Material & Methods: Study participants included elite youth judo athletes (n = 10, age 22.1 +- 2.8 years, weight 80.03 +- 11.8 kg, height 183.0 +- 4.2 cm) whose body composition was measured using bioelectrical impedance before and after pre-competitive weight loss (6 days on average, using dehydration).
We observed resistance, reactance, phase angle, and changes in total body water and its components and indirectly estimated parameters of body composition quality (lean body mass, body cell mass, fat mass, intracellular mass, ECM/BCM). Results: The results showed significant changes in directly measurable parameters of body composition (resistance, reactance, phase angle) due to intentional body weight reduction in judo athletes.
Resistance after weight reduction increased by 22.26 % (Mpre-test: 373.60 +- 34.94 Ω, Mpost-test: 480.60 +- 47.17 Ω, t9 = -8.44, p < 0.01, d = 0.96). We also detected significantly higher reactance (Mpre-test: 50.90 +- 6.52 Ω, Mpost-test: 59.60 +- 6.33 Ω, t9 = -9.11, p < 0.01, d = 1.05).
Due to a higher increase in resistance (22.26 %) in comparison to reactance (14.60 %), the phase angle decreased significantly (Mpre-test: 7.54 +- 0.91 o, Mpost-test: 7.24 +- 1.05 o t9 = 5.031, p < 0.01, d = 1.26). Conclusions: Significant changes in directly measurable parameters (resistance, reactance, phase angle) showed a change in total body water and its components, especially intracellular water.