Purpose: The aim of the present study was to compare the contributions of the anaerobic pathway as determined by two different methods and energy expenditure during a typical high-intensity intermittent exercise (HIIE) protocol. Methods: A descriptive research design was utilized in which thirteen physically active men performed six experimental sessions consisting of an incremental test (session 1), submaximal tests at 40, 50, 60, 70, 75, 80, 85, 90% of velocity associated with maximum oxygen uptake (v$\dot{\text{V}}$O_2max) with two intensities per session (sessions 2–5), and the HIIE protocol (session 6; 10 efforts of 1 min at v$\dot{\text{V}}$O_2max interspersed by 1 min of passive recovery). The estimation of anaerobic energy system contribution was calculated by: (a) the excess post-exercise oxygen consumption plus delta lactate method and (b) the accumulated oxygen deficit method using the difference between predicted oxygen demand from the submaximal tests of varying intensities and accumulated oxygen uptake during HIIE. Estimation of aerobic energy system contribution was calculated through the measurement of oxygen consumption during activity. Total EE during the entire HIIE protocol (efforts + recovery) and for the efforts only were calculated from each method. Results: For efforts + recovery and efforts only, anaerobic contribution was similar for both methods, and consequently total EE was also equivalent (p = 0.230 for both comparisons). During efforts + recovery, aerobic:anaerobic energy system contribution was (68 ± 4%: 32 ± 4%), while efforts only was (54 ± 5%: 46 ± 5%) with both situations demonstrating greater aerobic than anaerobic contribution (p < 0.001 for both). Conclusion: Anaerobic contribution seems to be relevant during HIIE and must to be taken into account during total EE estimation; however, the type of method employed did not change the anaerobic contribution or total EE estimates.

The aim of this study was to compare the perceptual and physiological responses and time‐to‐exhaustion in high intensity interval exercise (HIIE) protocols that are prescribed based on the relative anaerobic speed reserve (ASR) or maximal aerobic speed (MAS) in athletes with different ASR values, as well as the coefficient of variation (CV) of the abovementioned variables. Eleven long‐distance runners and ten rugby players were submitted to five experimental sessions on different days; the first and second session were intended for the determination of the anthropometry, MAS and maximal sprint (MSS). In the subsequent sessions, three HIIE_15:15s protocols were performed until exhaustion (110%MAS, Δ25%ASR, and Δ50%ASR) in random order. The anthropometric characteristics and variables obtained from the MAS and MSS tests in the different groups were compared by Student's unpaired t‐test. The analysis of mixed models for repeated measures (groups and protocols) was used to compare the speed, delta blood lactate, rating of perceived exertion, and time‐to‐exhaustion. Rugby players presented higher ASR (13.6 ± 0.9 km h⁻¹) compared to long‐distance runners (12.6 ± 0.9 km h⁻¹) (P = .049). For the HIIE_15:15s protocols, there were no protocol and group interaction effects. However, lower CV values were observed for time‐to‐exhaustion (a mean reduction of 52%) and delta blood lactate (a mean reduction of 48%) in Δ25%ASR and Δ50%ASR when compared to 110%MAS. Furthermore, the rating of perceived exertion CV was similar in all HIIE_15:15s protocols. The prescription of intensity of HIIE based on the ASR was able to reduce the inter‐subject variability of lactate and time‐to‐exhaustion in rugby players and long‐distance runners.

Durance with strength training) may result in negative interference on strength performance. Moreover, there are indications that the magnitude of this interference is dependent on endurance exercise mode. Thus, this study aimed to verify the acute effects of previous running and cycling on strength endurance performance. After the determination of the maximum intensity reached (Imax) during treadmill running and cycle ergometer pedaling and half-squat maximum strength (1 repetition maximum [1RM]), 10 physically active men were submitted to 3 experimental conditions: control condition (S) comprised of 4 sets of maximum repetitions at 80% 1RM, intermittent running (RS), and cycling (CS) conditions (15 × 1 minute:1 minute in the Imax) followed by the strength exercise (S). Maximum number of repetitions (MNR), total session volume (TV), and vastus lateralis electromyographic signal (VLRMS) were analyzed. It was observed that MNR and TV performed in set 1 in the S condition was superior to that performed in set 1 in the RS (p < 0.001) and CS (p < 0.001) conditions; and set 2 in the S condition was superior to set 2 only in the CS for the MNR (p = 0.032) and TV (p = 0.012). For the VLRMS, there was a main effect for repetition, with higher values in the last repetition compared with the second one (p < 0.01). In conclusion, an aerobic exercise bout before strength exercise impairs the subsequent strength endurance performance. In addition, the magnitude of the interference effect was higher after the aerobic cycling exercise....

Purpose: This study compared the energy system contributions and relationship between mechanical and energy system variables in upper and lower body Wingate tests (WAnT) in judo athletes. Method: Eleven male judo athletes (18 ± 1 years, 174.3 ± 5.3 cm, 72.6 ± 9.9 kg, 11.8 ± 1.7% body fat) attended two laboratory sessions to perform two WAnT (upper and lower body) and two incremental tests (upper and lower body). The energy contributions of the oxidative, glycolytic, and phosphagen (ATP-PCr) systems were estimated based on oxygen consumption ( $\dot{\mathrm{V}}{\mathrm{O}}_2$) during WAnT, delta of lactate, and the fast phase of excess $\dot{\mathrm{V}}{\mathrm{O}}_2$, respectively. Results: The upper and lower body presented similar results of oxidative (21 ± 4% vs 23 ± 3%) and ATP-PCr system contributions (29 ± 6% vs 32 ± 5%). The glycolytic system contribution (50 ± 5% vs 45 ± 4%) was higher in the upper body. The variance of mechanical variables in upper body was explained by glycolytic (R² = 0.49–0.62) and oxidative systems (R² = 0.44–0.49), whereas the variance of mechanical variables in lower body was explained by ATP-PCr (R² = 0.41–0.55) and glycolytic systems (R² = 0.62–0.94). Conclusions: During WAnT, the glycolytic system presented the major energy contribution, being higher in the upper body. Moreover, mechanical and energy system variables presented a distinct relationship when comparing upper and lower body WAnT.