Naroa Etxebarria

Relative Importance of Strength, Power, and Anthropometric Measures to Jump Performance of Elite Volleyball Players

The purpose of this investigation was to examine the potential strength, power, and anthropometric contributors to vertical jump performances that are considered specific to volleyball success: the spike jump (SPJ) and counter-movement vertical jump (CMVJ). To assess the relationship among strength, power, and anthropometric variables with CMVJ and SPJ, a correlation and regression analysis was performed. In addition, a comparison of strength, power, and anthropometric differences between the seven best subjects and the seven worst athletes on the CMVJ test and SPJ test was performed. When expressed as body mass relative measures, moderate correlations (0.53-0.65; p ≤ 0.01) were observed between the 1RM measures and both relative CMVJ and relative SPJ. Very strong correlations were observed between relative (absolute height-standing reach height) depth jump performance and relative SPJ (0.85; p ≤ 0.01) and relative CMVJ (0.93; p ≤ 0.01). The single best regression model component for relative CMVJ was the relative depth jump performance, explaining 84% of performance. The single best predictor for relative SPJ was also the relative depth jump performance (72% of performance), with the three-component models of relative depth jump, relative CMVJ, spike jump contribution (percent difference between SPJ and CMVJ), and relative CMVJ, spike jump contribution, and peak force, accounting for 96% and 97%, respectively. The results of this study clearly demonstrate that in an elite population of volleyball players, stretch-shortening cycle performance and the ability to tolerate high stretch loads, as in the depth jump, is critical to performance in the jumps associated with volleyball performance.

VALIDATION OF HEART RATE MONITOR-BASED PREDICTIONS OF OXYGEN UPTAKE AND ENERGY EXPENDITURE

Montgomery, PG, Green, DJ, Etxebarria, N, Pyne, DB, Saunders, PU, and Minahan, CL. Validation of heart rate monitor-based predictions of oxygen uptake and energy expenditure. J Strength Cond Res 23(5): 1489-1495, 2009-To validate &OV0312;o2 and energy expenditure predictions by the Suunto heart rate (HR) system against a first principle gas analysis system, well-trained male (n = 10, age 29.8 ± 4.3 years, &OV0312;o2 65.9 ± 9.7 ml·kg−1·min−1) and female (n = 7, 25.6 ± 3.6 years, 57.0 ± 4.2 ml·kg−1·min−1) runners completed a 2-stage incremental running test to establish submaximal and maximal oxygen uptake values. Metabolic cart values were used as the criterion measure of &OV0312;o2 and energy expenditure (kJ) and compared with the predicted values from the Suunto software. The 3 levels of software analysis for the Suunto system were basic personal information (BI), BI + measured maximal HR (BIhr), and BIhr + measured &OV0312;o2 (BIhr + v). Comparisons were analyzed using linear regression to determine the standard error of the estimate (SEE). Eight subjects repeated the trial within 7 days to determine reliability (typical error [TE]). The SEEs for oxygen consumption via BI, BIhr, and BIhr + v were 2.6, 2.8, and 2.6 ml·kg−1·min−1, respectively, with corresponding percent coefficient of variation (%CV) of 6.0, 6.5, and 6.0. The bias compared with the criterion &OV0312;o2 decreased from −6.3 for BI, −2.5 for BIhr, to −0.9% for BIhr + v. The SEE of energy expenditure improved from BI (6.74 kJ) to BIhr (6.56) and BIhr + v (6.14) with corresponding %CV of 13.6, 12.2, and 12.7. The TE values for &OV0312;o2 were ∼0.60 ml·kg−1·min−1 and ∼2 kJ for energy expenditure. The %CV for &OV0312;o2 and energy expenditure was ∼1 to 4%. Although reliable, basic HR-based estimations of &OV0312;o2 and energy expenditure from the Suunto system underestimated &OV0312;o2 and energy expenditure by ∼6 and 13%, respectively. However, estimation can be improved when maximal HR and &OV0312;o2 values are added to the software analysis.

High-intensity cycle interval training improves cycling and running performance in triathletes

Abstract Effective cycle training for triathlon is a challenge for coaches. We compared the effects of two variants of cycle high-intensity interval training (HIT) on triathlon-specific cycling and running. Fourteen moderately-trained male triathletes (O2peak 58.7 ± 8.1 mL kg−1 min−1; mean ± SD) completed on separate occasions a maximal incremental test (O2peak and maximal aerobic power), 16 × 20 s cycle sprints and a 1-h triathlon-specific cycle followed immediately by a 5 km run time trial. Participants were then pair-matched and assigned randomly to either a long high-intensity interval training (LONG) (6–8 × 5 min efforts) or short high-intensity interval training (SHORT) (9–11 × 10, 20 and 40 s efforts) HIT cycle training intervention. Six training sessions were completed over 3 weeks before participants repeated the baseline testing. Both groups had an ∼7% increase in O2peak (SHORT 7.3%, ±4.6%; mean, ±90% confidence limits; LONG 7.5%, ±1.7%). There was a moderate improvement in mean power for both the SHORT (10.3%, ±4.4%) and LONG (10.7%, ±6.8%) groups during the last eight 20-s sprints. There was a small to moderate decrease in heart rate, blood lactate and perceived exertion in both groups during the 1-h triathlon-specific cycling but only the LONG group had a substantial decrease in the subsequent 5-km run time (64, ±59 s). Moderately-trained triathletes should use both short and long high-intensity intervals to improve cycling physiology and performance. Longer 5-min intervals on the bike are more likely to benefit 5 km running performance.

Vascular Occlusion and Sequential Compression for Recovery After Resistance Exercise

Abstract Northey, JM, Rattray, B, Argus, CK, Etxebarria, N, and Driller, MW. Vascular occlusion and sequential compression for recovery after resistance exercise. J Strength Cond Res 30(2): 533–539, 2016—The purpose of this study was to evaluate vascular occlusion (OCC) and sequential intermittent pneumatic compression (SIPC) as recovery strategies after fatiguing resistance exercise. Twelve strength-trained male participants (age: 24.0 ± 6.3 years, height: 180.4 ± 9.7 cm, and weight: 84.8 ± 9.6 kg) participated in a randomized cross-over study. Participants performed a fatiguing resistance exercise bout consisting of 10 sets with 10 repetitions of back squats at 70% 1 repetition maximum with 3-minute rest between sets. Outcome measures of perceived recovery status, muscle soreness, concentric peak isokinetic torque of the quadriceps, squat jump (SJ) height, and countermovement jump (CMJ) height were taken before the fatiguing resistance exercise bout and repeated immediately post, 1 hour, and 24 hours later. Immediately after the postexercise measures, participants undertook 1 of the 3 recovery strategies: OCC, SIPC, and a passive control (CON). Concentric peak isokinetic torque of the quadriceps was decreased significantly immediately post and 1 hour after the fatiguing resistance exercise bout compared with baseline values (p ⩽ 0.05). Mean SJ and CMJ jump height decreased significantly immediately post and 1 hour compared with baseline measures, but only the SJ was significantly decreased at 24 hours. There were no significant differences between conditions for any of the postexercise measures (p > 0.05). In conclusion, this study indicates that OCC and SIPC are not effective for attenuating muscle performance loss after a fatiguing resistance exercise bout relative to passive recovery.

Physiological assessment of isolated running does not directly replicate running capacity after triathlon-specific cycling

Abstract Triathlon running is affected by prior cycling and power output during triathlon cycling is variable in nature. We compared constant and triathlon-specific variable power cycling and their effect on subsequent submaximal running physiology. Nine well-trained male triathletes (age 24.6 ± 4.6 years, 4.5 ± 0.4 L · min−1; mean ± SD) performed a submaximal incremental run test, under three conditions: no prior exercise and after a 1 h cycling trial at 65% of maximal aerobic power with either a constant or a variable power profile. The variable power protocol involved multiple 10–90 s intermittent efforts at 40–140% maximal aerobic power. During cycling, pulmonary ventilation (22%, ±14%; mean; ±90% confidence limits), blood lactate (179%, ±48%) and rating of perceived exertion (7.3%, ±10.2%) were all substantially higher during variable than during constant power cycling. At the start of the run, blood lactate was 64%, ±61% higher after variable compared to constant power cycling, which decreased running velocity at 4 mM lactate threshold by 0.6, ±0.9 km · h−1. Physiological responses to incremental running are negatively affected by prior cycling and, to a greater extent, by variable compared to even-paced cycling. Testing and training of triathletes should account foe higher physiological cost of triathlon-specific cycling and its effect on subsequent running.

Variability in Power Output During Cycling in International Olympic-Distance Triathlon

PURPOSE The patterns of power output in the ~1-h cycle section of Olympic-distance triathlon races are not well documented. Here the authors establish a typical cycling-race profile derived from several International Triathlon Union elite-level drafting-legal triathlon races. METHODS The authors collated 12 different race power profiles from elite male triathletes (N = 5, age 25 ± 5 y, body mass 65.5 ± 5.6 kg; mean ± SD) during 7 international races. Power output was recorded using SRM cranks and analyzed with proprietary software. RESULTS The mean power output was 252 ± 33 W, or 3.9 ± 0.5 W/kg in relative terms, with a coefficient of variation of 71% ± 13%. Normalized power (power output an athlete could sustain if intensity were maintained constant without any variability) for the entire cycle section was 291 ± 29 W, or 40 ± 13 W higher than the actual mean power output. There were 34 ± 14 peaks of power output above 600 W and ~18% time spent at >100% of maximal aerobic power. CONCLUSION Cycling during Olympic-distance triathlon, characterized by frequent and large power variations including repeat supramaximal efforts, equates to a higher workload than cycling at constant power.