Comparison Of Running Energy Reserve Index Of Sprint, Endurance And Untrained Participants

Running Energy Reserve Index (RERI) has been proven to be an accurate method in predicting run performances from sprint to middle distance (Balasekaran et al., 2011). However, none of the studies have investigated if RERI could differentiate between sprint trained, endurance trained and untrained participants PURPOSE: To compare RERI among endurance trained (ET), sprint trained (ST) athletes and untrained (UT) participants. METHODS: Nine ST (age = 26.89±9.39 years, %BF = 10.59±2.55, BMI = 23.09±2.07 kg.m-2, V†O2max = 51.12±3.59 ml.kg-1.min-1), 12 ET (age = 31.67±7.24 years, %BF = 12.74±2.38, BMI = 21.34±1.27 kg.m-2, V†O2max = 57.62±5.40 ml.kg-1.min-1) athletes and 17 UT (age = 29.76±7.89 years, %BF = 18.32±4.17, BMI = 23.47±2.04 kg.m-2, V†O2max = 46.86±3.76 ml.kg-1.min-1) participants were recruited. RERI is a ratio of maximal aerobic energy (EMAS) and maximal anaerobic energy (EMAnS) corresponding to maximal anaerobic speed (MAnS) and maximal aerobic speed (MAS). To determine MAS, athletes performed six laboratory tests which were as follows: Astrand modified running protocol, submaximal discontinuous treadmill (SUBMAX) protocol, O2 till exhaustion (Tlim) tests at vV†O2max and at Vsub%95 (νΔ50 or νΔ50+5%vV†O2max), and speed and duration curve protocol. To determine the maximal anaerobic speed (MAnS), athletes performed a 50 m sprint run test on the track. The EMAS and EMAnS were determined at corresponding maximal speeds, MAnS and MAS, with a submaximal efficiency equation. STATISTICS: A linear regression analysis was employed to determine vLT, and the speed–V†O2 relationship to calculate vV†O2max, EMAS, and EMAnS.Analysis of variance statistical test was employed to compare RERI among ET, UT and ST participants. RESULTS: The VO2max, %BF, and BMI was significantly different between the ET, ST and UT groups (P<0.05). The RERI of UT (2.29±0.18) was significantly higher than ET (1.85±0.14) athletes and significantly lower than ST athletes (2.65±0.13; ST>UT