Abstract
This descriptive study aimed to explore the physiological factors that determine tolerance to exertion during high-intensity interval effort. Forty-seven young women (15–28 years old) were enrolled: 23 athletes from Taiwan national or national reserve teams and 24 moderately active females. Each participant underwent a maximal incremental INC (modified Bruce protocol) cardiopulmonary exercise test on the first day and high-intensity interval testing (HIIT) on the second day, both performed on a treadmill. The HIIT protocol involved alternation between 1-min effort at 120% of the maximal speed, at the same slope reached at the end of the INC, and 1-min rest until volitional exhaustion. Gas exchange, heart rate (HR), and muscle oxygenation at the right vastus lateralis, measured by near-infrared spectroscopy, were continuously recorded. The number of repetitions completed (Rlim) by each participant was considered the HIIT tolerance index. The results showed a large difference in the Rlim (range, 2.6–12.0 repetitions) among the participants. Stepwise linear regression revealed that the variance in the Rlim within the cohort was related to the recovery rates of oxygen consumption (), HR at the second minute after INC, and muscle tissue saturation index at exhaustion (R = 0.644). In addition, age was linearly correlated with Rlim (adjusted R = −0.518, p < 0.0001). In conclusion, the recovery rates for and HR after the incremental test, and muscle saturation index at exhaustion, were the major physiological factors related to HIIT performance. These findings provide insights into the role of the recovery phase after maximal INC exercise testing. Future research investigating a combination of INC and HIIT testing to determine training-induced performance improvement is warranted.
Citation: Chang S-C, Adami A, Lin H-C, Lin Y-C, Chen CPC, Fu T-C, et al. (2020) Relationship between maximal incremental and high-intensity interval exercise performance in elite athletes. PLoS ONE 15(5):
e0226313.
https://doi.org/10.1371/journal.pone.0226313
Editor: Juan M. Murias, University of Calgary, CANADA
Received: November 21, 2019; Accepted: April 27, 2020; Published: May 12, 2020
Copyright: © 2020 Chang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript and its Supporting Information files.
Funding: This research was supported by (1) Ministry of Science and Technology (Grant No. 104-2314-B-182A-045-MY2 and 106-2314-B-182A-134-MY3, https://www.most.gov.tw/?l=de) (2)Chang Gung Memorial Hospital (grant No. CMRPG3E1561/2, http://www.chang-gung.com/en/) to Shu-Chun Huang and (3) Healthy Aging Research Center, Chang Gung University and the Taiwan Ministry of Education's Higher Education Deep Plowing Program (Grant Numbers EMRPD1H0351 and EMRPD1H0551, http://www.cgu.edu.tw/bin/home.php?Lang=en) to Shu-Chun Huang.
Competing interests: The authors have declared that no competing interests exist.
Abbreviations:
Ath,
athletes; ATT,
adipose tissue thickness; BCM,
body cell mass; EqCO2,
ventilatory equivalent for CO2; EqO2,
ventilatory equivalent for O2; FFM,
fat free mass; HHb,
deoxy-(hemoglobin+myoglobin); HR,
heart rate; HRmax,
maximal HR; HR reserve,
heart rate reserve; ΔHR0.5,
HRmax − HR at 0.5 min recovery; ΔHR1,
HRmax − HR at 1 min recovery; ΔHR2,
HRmax − HR at 2 min recovery; ΔHR0.5/,
ΔHR0.5/HRmax; ΔHR1/,
ΔHR1/HRmax; ΔHR2/,
ΔHR2/HRmax; HRrt1/2,
time span the heart rate recovers to half; HIIT,
high-intensity interval testing; INC,
maximal incremental exercise test; MA,
moderately active participants; Max O2 pulse,
maximal /HR; NIRS,
near-infrared spectroscopy; O2Hb,
oxy-(hemoglobin+myoglobin); ΔO2Hb0.5,
O2Hb at 0.5 min during recovery − peak O2Hb; ΔO2Hb1,
O2Hb at 1 min during recovery − peak O2Hb; ΔO2Hb2,
O2Hb at 2 min during recovery − peak O2Hb; ΔO2Hb0.5/,
ΔO2Hb0.5/(maximal O2Hb − minimal O2Hb) during recovery; ΔO2Hb1 /,
ΔO2Hb1/(maximal O2Hb − minimal O2Hb) during recovery; ΔO2Hb2/,
ΔO2Hb2/(maximal O2Hb − minimal O2Hb) during recovery; PBF,
percent body fat; PCr,
phosphocreatine; Rlim,
number of total repetitions to limitation (i.e., exhaustion) in high-intensity interval exercise test; SLM,
soft lean mass; SMM,
skeletal muscle mass; SMLA,
segmental muscle mass, left arm; SMLL,
segmental muscle mass, left leg; SMRA,
segmental muscle mass, right arm; SMRL,
segmental muscle mass, right leg; SMTR,
segmental muscle mass, trunk; TBM/FFM,
total body mass/fat free mass; T1/2,
the time span the variable changes in half; THb,
total-(hemoglobin+myoglobin); TSI,
tissue saturation index; TSIINC,
tissue saturation index at exhaustion (immediately before recovery) during INC; ΔTSI0.5,
TSI at 0.5 min during INC recovery − peak TSI; ΔTSI1,
TSI at 1 min during INC recovery − peak TSI; ΔTSI2,
TSI at 2 min during INC recovery − peak TSI; ΔTSI0.5/,
ΔTSI0.5/(maximal TSI − minimal TSI) during recovery; ΔTSI1 /,
ΔTSI1/(maximal TSI − minimal TSI) during recovery; ΔTSI2/,
ΔTSI2/(maximal TSI − minimal TSI) during recovery; ,
rate of carbon dioxide production; ,
minute ventilation; ,
rate of oxygen consumption; ,
maximal ; ,
− at 0.5 min recovery; ,
− at 1 min recovery; ,
− at 2 min recovery; /,
/maximal ; /,
/maximal ; /,
/maximal ; /maximal ,
time span the recovers to half