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Horiuchi M, Saito A, Motoyama K, Tashiro T, Abe D. Normalized economical speed is influenced by aging and not by exercise habituation. BMC Res Notes 2023; 16:254. [PMID: 37798737 PMCID: PMC10557329 DOI: 10.1186/s13104-023-06545-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 09/28/2023] [Indexed: 10/07/2023] Open
Abstract
OBJECTIVE A U-shaped relationship between energy cost of walking (Cw) and walking speed indicates that there is a specific speed minimizing the Cw, called economical speed (ES). It is mostly slower in older adults than young adults; however, effects of leg length on the ES have been ignored. We investigated effects of aging and exercise habituation on the normalized ES by leg length (ESnormalized). We quantified time delay of stride length and step frequency in sedentary young (SY), active young (AY), and active elderly (AE) adults in response to sinusoidal gait speed change at 30-s and 180-s periods with an amplitude of ± 0.56 m・s- 1. RESULTS The ES was significantly slower in the following sequence: AE, SY, and AY, whereas ESnormalized was slower in the AE than in other young groups, with no difference between AY and SY. AE and SY showed greater step variabilities at the 180-s period, whereas AY showed relatively smaller step variabilities at both periods. Collectively, the ESnormalized slowed due to aging, not due to exercise habituation. When optimizing the appropriate SL-SF combination for sinusoidal speed changes, young and elderly adults may adopt different strategies. Exercise habituation may reduce step variabilities in young adults.
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Affiliation(s)
- Masahiro Horiuchi
- National Institute of Fitness and Sports in KANOYA, Shiromizu-1, Kanoya-shi, Kagoshima, 891-2393 Japan
| | - Akira Saito
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka, 813-8503 Japan
| | - Kiyotaka Motoyama
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka, 813-8503 Japan
| | - Takehiro Tashiro
- CNP Design, 4-1-5 Shimobaru, Higashi-ku, Fukuoka, 813-0002 Japan
| | - Daijiro Abe
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka, 813-8503 Japan
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Fujita M, Kamibayashi K, Horiuchi M, Ebine N, Fukuoka Y. Alterations in step frequency and muscle activities using body weight support influence the ventilatory response to sinusoidal walking in humans. Sci Rep 2023; 13:15534. [PMID: 37726511 PMCID: PMC10509255 DOI: 10.1038/s41598-023-42811-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/14/2023] [Indexed: 09/21/2023] Open
Abstract
The use of body weight support (BWS) can reveal important insights into the relationship between lower-limb muscle activities and the ventilatory response during sinusoidal walking. Here, healthy participants (n = 15) walked on a treadmill while 0%, 30%, and 50% of their body weight was supported with BWS. The walking speed was varied sinusoidally between 3 and 6 km h-1, and three different frequencies, and periods ranging from 2 to 10 min were used. Breath-by-breath ventilation ([Formula: see text]) and CO2 output ([Formula: see text]) were measured. The tibialis anterior (TA) muscle activity was measured by electromyography throughout the walking. The amplitude (Amp), normalized Amp [Amp ratio (%)], and phase shift (PS) of the sinusoidal variations in measurement variables were calculated using a Fourier analysis. The results revealed that the Amp ratio in [Formula: see text] increased with the increase in BWS. A steeper slope of the [Formula: see text]-[Formula: see text] relationship and greater [Formula: see text]/[Formula: see text] values were observed under reduced body weight conditions. The Amp ratio in TA muscle was significantly positively associated with the Amp ratio in the [Formula: see text] (p < 0.001). These findings indicate that the greater amplitude in the TA muscle under BWS may have been a potent stimulus for the greater response of ventilation during sinusoidal walking.
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Affiliation(s)
- Mako Fujita
- Faculty of Health and Sports Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Kiyotaka Kamibayashi
- Faculty of Health and Sports Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Masahiro Horiuchi
- National Institute of Fitness and Sports in Kanoya, Kagoshima, Japan
| | - Naoyuki Ebine
- Faculty of Health and Sports Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan.
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Abe D, Tashiro T, Motoyama K, Horiuchi M, Saito A. Gait variability of interlimb coordination in high-heeled shoes with detachable base sockets under conditions of sinusoidal speed change. Gait Posture 2023; 106:80-85. [PMID: 37672967 DOI: 10.1016/j.gaitpost.2023.08.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 04/13/2023] [Accepted: 08/30/2023] [Indexed: 09/08/2023]
Abstract
BACKGROUND This study aimed to investigate the effects of wearing high-heeled shoes (HHS) on gait variability of the lower limbs when the treadmill speed was sinusoidally changed. METHODS A total of 17 young females walked on a treadmill with HHS, HHS with detachable base sockets (HHS-Sockets), and low-heeled shoes (LHS) under sinusoidal speed-changing protocol of 60-s and 30-s periods with an amplitude of ± 0.56 m·s-1. The time course of the joint elevation angles of the thigh, shank, and foot in one gait cycle can be well approximated like a plane in a triaxial space, so-called intersegmental coordination (IC). Standard deviation of the plane (IC thickness) was considered as the anteroposterior gait variability when the best-fitting plane of the angular covariation was obtained. The lateral gait variability was the coefficient of variance of step width (CVSW). To examine whether the gait parameters was associated with IC thickness, a sum of the time delay of the stride length and step frequency (TDSL+SF) against sinusoidal speed change was calculated. RESULTS The IC thickness was not different across shoe conditions and periods. The CVSW was greater in the HHS and HHS-Sockets conditions than in the LHS condition. TDSL+SF was greater in the HHS condition than in the LHS and HHS-Sockets conditions at both periods; however, it was not correlated with IC thickness. SIGNIFICANCE Walking with HHS increased lateral gait variability at faster speed-changing situation, but not anteroposterior gait variability. Detachable sockets expanding the base area ten times greater than that of HHS could reduce TDSL+SF; however, TDSL+SF could not explain the IC thickness.
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Affiliation(s)
- Daijiro Abe
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka 813-8503, Japan.
| | - Takehiro Tashiro
- CNP Design, 4-1-5 Shimobaru, Higashi-ku, Fukuoka 813-0002, Japan
| | - Kiyotaka Motoyama
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka 813-8503, Japan
| | - Masahiro Horiuchi
- Faculty of Sports and Life Science, School of Physical Education, National Institute of Fitness and Sports in KANOYA, Kanoya, Kagoshima, Japan
| | - Akira Saito
- Center for Health and Sports Science, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka 813-8503, Japan
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Ward AMM, Guluzade NA, Kowalchuk JM, Keir DA. Coupling of [Formula: see text] and [Formula: see text] kinetics: insights from multiple exercise transitions below the estimated lactate threshold. Eur J Appl Physiol 2023; 123:509-522. [PMID: 36371597 DOI: 10.1007/s00421-022-05073-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 10/10/2022] [Indexed: 11/13/2022]
Abstract
During a step-change in exercise power output (PO), ventilation ([Formula: see text]) increases with a similar time course to the rate of carbon dioxide delivery to the lungs ([Formula: see text]). To test the strength of this coupling, we compared [Formula: see text] and [Formula: see text] kinetics from ten independent exercise transitions performed within the moderate-intensity domain. Thirteen males completed 3-5 repetitions of ∆40 W step transitions initiated from 20, 40, 60, 80, 100, and 120 W on a cycle ergometer. Preceding the ∆40 W step transitions from 60, 80, 100, and 120 W was a 6 min bout of 20 W cycling from which the transitions of variable ∆PO were examined. Gas exchange ([Formula: see text] and oxygen uptake, [Formula: see text]) and [Formula: see text] were measured by mass spectrometry and volume turbine. The kinetics of the responses were characterized by the time constant (τ) and amplitude (Δ[Formula: see text]/Δ[Formula: see text]). Overall, [Formula: see text] kinetics were consistently slower than [Formula: see text] kinetics (by ~ 45%) and τ[Formula: see text] rose progressively with increasing baseline PO and with heightened ∆PO from a common baseline. Compared to τ[Formula: see text], τ[Formula: see text] was on average slightly greater (by ~ 4 s). Repeated-measures analysis of variance revealed that there was no interaction between τ[Formula: see text] and τ[Formula: see text] in either the variable baseline (p = 0.49) and constant baseline (p = 0.56) conditions indicating that each changed in unison. Additionally, for Δ[Formula: see text]/Δ[Formula: see text], there was no effect of either variable baseline PO (p = 0.05) or increasing ΔPO (p = 0.16). These data provide further evidence that, within the moderate-intensity domain, both the temporal- and amplitude-based characteristics of V̇E kinetics are inextricably linked to those of [Formula: see text].
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Affiliation(s)
- Alexandra M M Ward
- School of Kinesiology, The University of Western Ontario, 1151 Richmond Street, London, ON, N6A 3K7, Canada
| | - Nasimi A Guluzade
- School of Kinesiology, The University of Western Ontario, 1151 Richmond Street, London, ON, N6A 3K7, Canada
| | - John M Kowalchuk
- School of Kinesiology, The University of Western Ontario, 1151 Richmond Street, London, ON, N6A 3K7, Canada.,Department of Physiology and Pharmacology, The University of Western Ontario, London, ON, Canada
| | - Daniel A Keir
- School of Kinesiology, The University of Western Ontario, 1151 Richmond Street, London, ON, N6A 3K7, Canada. .,Toronto General Research Institute, Toronto General Hospital, Toronto, ON, Canada.
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Fujita M, Kamibayashi K, Aoki T, Horiuchi M, Fukuoka Y. Influence of Step Frequency on the Dynamic Characteristics of Ventilation and Gas Exchange During Sinusoidal Walking in humans. Front Physiol 2022; 13:820666. [PMID: 35492612 PMCID: PMC9039249 DOI: 10.3389/fphys.2022.820666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/14/2022] [Indexed: 11/17/2022] Open
Abstract
We tested the hypothesis that restricting either step frequency (SF) or stride length (SL) causes a decrease in ventilatory response with limited breath frequency during sinusoidal walking. In this study, 13 healthy male and female volunteers (mean ± SD; age: 21.5 ± 1.8 years, height: 168 ± 7 cm, weight: 61.5 ± 8.3 kg) participated. The walking speed was sinusoidally changed between 50 and 100 m⋅min–1 with periods from 10 to 1 min. Using a customized sound system, we fixed the SF at 120 steps⋅min–1 with SL variation (0.83–0.41 m) (SFfix) or fixed the SL at 0.7 m with SF variation (143–71 steps⋅min–1) (SLfix) during the subjects’ sinusoidal walking. Both the subjects’ preferred locomotion pattern without a sound system (Free) and the unprompted spontaneous locomotor pattern for each subject (Free) served as the control condition. We measured breath-by-breath ventilation [tidal volume (VT) and breathing frequency (Bf)] and gas exchange [CO2 output (V.CO2), O2 uptake (V.O2)]. The amplitude (Amp) and the phase shift (PS) of the fundamental component of the ventilatory and gas exchange variables were calculated. The results revealed that the SFfix condition decreased the Amp of the Bf response compared with SLfix and Free conditions. Notably, the Amp of the Bf response under SFfix was reduced by less than one breath at the periods of 5 and 10 min. In contrast, the SLfix condition resulted in larger Amps of Bf and V.E responses as well as Free. We thus speculate that the steeper slope of the V.E-V.CO2 relationship observed under the SLfix might be attributable to the central feed-forward command or upward information from afferent neural activity by sinusoidal locomotive cadence. The PSs of the V.E, V.O2, and V.CO2 responses were unaffected by any locomotion patterns. Such a sinusoidal wave manipulation of locomotion variables may offer new insights into the dynamics of exercise hyperpnea.
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Affiliation(s)
- Mako Fujita
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
| | | | - Tomoko Aoki
- Faculty of Environmental Symbiotic Science, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Masahiro Horiuchi
- Division of Human Environmental Science, Mt. Fuji Research Institute, Fujiyoshida, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
- *Correspondence: Yoshiyuki Fukuoka,
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Girardi M, Gattoni C, Mauro L, Capelli C. The effects of sinusoidal linear drifts on the estimation of cardiorespiratory dynamic parameters during sinusoidal workload forcing: a simulation study. Respir Physiol Neurobiol 2021; 289:103652. [PMID: 33677090 DOI: 10.1016/j.resp.2021.103652] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/20/2021] [Accepted: 02/26/2021] [Indexed: 11/15/2022]
Abstract
This study aimed at investigating whether: 1) different sinusoidal linear drifts would affect the estimation of the dynamic parameters amplitude (A) and phase lag (φ) of minute ventilation (V˙E), oxygen uptake, carbon dioxide production and heart rate (HR) sinusoidal responses when the frequency analysis technique (F) is performed; 2) the Marquardt-Levenberg non-linear fitting technique (ML) would provide more precise estimations of A and φ of drifted sinusoidal responses compared to F. For each cardiorespiratory variable, fifteen responses to sinusoidal forcing of different sinusoidal periods were simulated by using a first-order dynamic linear model. A wide range of linear drifts were subsequently applied. A and φ were computed for all drifted and non-drifted responses by using both F (AF and φF) and ML (AML and φML). For non-drifted responses, no differences between AF vs AML and φF vs φML were found. Whereas AF and φF were affected by the sinusoidal linear drifts, AML and φML were not. Significant interaction effects (technique x drift) were found for A (P < 0.001; ƞP2 > 0.247) and φ (P < 0.001; ƞP2 > 0.851). Higher goodness of fit values were observed when using ML for drifted V˙E and HR responses only. The present findings suggest ML as a recommended technique to use when sinusoidal linear drifts occur during sinusoidal exercise, and provide new insights on how to analyse drifted cardiorespiratory sinusoidal responses.
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Affiliation(s)
- Michele Girardi
- Centre for Brain Science, Department of Psychology, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom.
| | - Chiara Gattoni
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, ME4 4AG, United Kingdom
| | - Lorenzo Mauro
- Department of Computer, Control and Management Engineering, University of Rome "La Sapienza", via Ariosto 25, 00185, Rome, Italy
| | - Carlo Capelli
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, via Felice Casorati 43, 1-37131, Verona, Italy
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Application of Molecular Hydrogen as an Antioxidant in Responses to Ventilatory and Ergogenic Adjustments during Incremental Exercise in Humans. Nutrients 2021; 13:nu13020459. [PMID: 33573133 PMCID: PMC7911623 DOI: 10.3390/nu13020459] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 11/16/2022] Open
Abstract
We investigated effects of molecular hydrogen (H2) supplementation on acid-base status, pulmonary gas exchange responses, and local muscle oxygenation during incremental exercise. Eighteen healthy, trained subjects in a randomized, double-blind, crossover design received H2-rich calcium powder (HCP) (1500 mg/day, containing 2.544 µg/day of H2) or H2-depleted placebo (1500 mg/day) for three consecutive days. They performed cycling incremental exercise starting at 20-watt work rate, increasing by 20 watts/2 min until exhaustion. Breath-by-breath pulmonary ventilation (V˙E) and CO2 output (V˙CO2) were measured and muscle deoxygenation (deoxy[Hb + Mb]) was determined via time-resolved near-infrared spectroscopy in the vastus lateralis (VL) and rectus femoris (RF). Blood gases' pH, lactate, and bicarbonate (HCO3-) concentrations were measured at rest and 120-, 200-, and 240-watt work rates. At rest, the HCP group had significantly lower V˙E, V˙CO2, and higher HCO3-, partial pressures of CO2 (PCO2) versus placebo. During exercise, a significant pH decrease and greater HCO3- continued until 240-watt workload in HCP. The V˙E was significantly lower in HCP versus placebo, but HCP did not affect the gas exchange status of V˙CO2 or oxygen uptake (V˙O2). HCP increased absolute values of deoxy[Hb + Mb] at the RF but not VL. Thus, HCP-induced hypoventilation would lead to lower pH and secondarily impaired balance between O2 delivery and utilization in the local RF during exercise, suggesting that HCP supplementation, which increases the at-rest antioxidant potential, affects the lower ventilation and pH status during incremental exercise. HPC induced a significantly lower O2 delivery/utilization ratio in the RF but not the VL, which may be because these regions possess inherently different vascular/metabolic control properties, perhaps related to fiber-type composition.
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Liu H, Leng B, Li Q, Liu Y, Bao D, Cui Y. The Effect of Eight-Week Sprint Interval Training on Aerobic Performance of Elite Badminton Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18020638. [PMID: 33451086 PMCID: PMC7828502 DOI: 10.3390/ijerph18020638] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/27/2020] [Accepted: 01/08/2021] [Indexed: 11/25/2022]
Abstract
This study was aimed to: (1) investigate the effects of physiological functions of sprint interval training (SIT) on the aerobic capacity of elite badminton players; and (2) explore the potential mechanisms of oxygen uptake, transport and recovery within the process. Thirty-two elite badminton players volunteered to participate and were randomly divided into experimental (Male-SIT and Female-SIT group) and control groups (Male-CON and Female-CON) within each gender. During a total of eight weeks, SIT group performed three times of SIT training per week, including two power bike trainings and one multi-ball training, while the CON group undertook two Fartlek runs and one regular multi-ball training. The distance of YO-YO IR2 test (which evaluates player’s ability to recover between high intensity intermittent exercises) for Male-SIT and Female-SIT groups increased from 1083.0 ± 205.8 m to 1217.5 ± 190.5 m, and from 725 ± 132.9 m to 840 ± 126.5 m (p < 0.05), respectively, which were significantly higher than both CON groups (p < 0.05). For the Male-SIT group, the ventilatory anaerobic threshold and ventilatory anaerobic threshold in percentage of VO2max significantly increased from 3088.4 ± 450.9 mL/min to 3665.3 ± 263.5 mL/min (p < 0.05),and from 74 ± 10% to 85 ± 3% (p < 0.05) after the intervention, and the increases were significantly higher than the Male-CON group (p < 0.05); for the Female-SIT group, the ventilatory anaerobic threshold and ventilatory anaerobic threshold in percentage of VO2max were significantly elevated from 1940.1 ± 112.8 mL/min to 2176.9 ± 78.6 mL/min, and from 75 ± 4% to 82 ± 4% (p < 0.05) after the intervention, which also were significantly higher than those of the Female-CON group (p < 0.05). Finally, the lactate clearance rate was raised from 13 ± 3% to 21 ± 4% (p < 0.05) and from 21 ± 5% to 27 ± 4% for both Male-SIT and Female-SIT groups when compared to the pre-test, and this increase was significantly higher than the control groups (p < 0.05). As a training method, SIT could substantially improve maximum aerobic capacity and aerobic recovery ability by improving the oxygen uptake and delivery, thus enhancing their rapid repeated sprinting ability.
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Affiliation(s)
- Haochong Liu
- China Institute of Sport and Health Science, Beijing Sport University, Beijing 100084, China; (H.L.); (Y.L.)
| | - Bo Leng
- Sports Coaching College, Beijing Sport University, Beijing 100084, China; (B.L.); (Q.L.)
| | - Qian Li
- Sports Coaching College, Beijing Sport University, Beijing 100084, China; (B.L.); (Q.L.)
| | - Ye Liu
- China Institute of Sport and Health Science, Beijing Sport University, Beijing 100084, China; (H.L.); (Y.L.)
| | - Dapeng Bao
- China Institute of Sport and Health Science, Beijing Sport University, Beijing 100084, China; (H.L.); (Y.L.)
- Correspondence: (D.B.); (Y.C.)
| | - Yixiong Cui
- AI Sports Engineering Lab, School of Sports Engineering, Beijing Sport University, Beijing 100084, China
- Correspondence: (D.B.); (Y.C.)
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Nicolò A, Girardi M, Bazzucchi I, Felici F, Sacchetti M. Respiratory frequency and tidal volume during exercise: differential control and unbalanced interdependence. Physiol Rep 2018; 6:e13908. [PMID: 30393984 PMCID: PMC6215760 DOI: 10.14814/phy2.13908] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 10/02/2018] [Accepted: 10/03/2018] [Indexed: 01/14/2023] Open
Abstract
Differentiating between respiratory frequency (fR ) and tidal volume (VT ) may improve our understanding of exercise hyperpnoea because fR and VT seem to be regulated by different inputs. We designed a series of exercise manipulations to improve our understanding of how fR and VT are regulated during exercise. Twelve cyclists performed an incremental test and three randomized experimental sessions in separate visits. In two of the three experimental visits, participants performed a moderate-intensity sinusoidal test followed, after recovery, by a moderate-to-severe-intensity sinusoidal test. These two visits differed in the period of the sinusoid (2 min vs. 8 min). In the third experimental visit, participants performed a trapezoidal test where the workload was self-paced in order to match a predefined trapezoidal template of rating of perceived exertion (RPE). The results collectively reveal that fR changes more with RPE than with workload, gas exchange, VT or the amount of muscle activation. However, fR dissociates from RPE during moderate exercise. Both VT and minute ventilation ( V ˙ E ) showed a similar time course and a large correlation with V ˙ CO 2 in all the tests. Nevertheless, V ˙ CO 2 was associated more with V ˙ E than with VT because VT seems to adjust continuously on the basis of fR levels to match V ˙ E with V ˙ CO 2 . The present findings provide novel insight into the differential control of fR and VT - and their unbalanced interdependence - during exercise. The emerging conceptual framework is expected to guide future research on the mechanisms underlying the long-debated issue of exercise hyperpnoea.
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Affiliation(s)
- Andrea Nicolò
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
| | - Michele Girardi
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
| | - Ilenia Bazzucchi
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
| | - Francesco Felici
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
| | - Massimo Sacchetti
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
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Ebine N, Ahad-Abdulkarim-D A, Miyake Y, Hojo T, Abe D, Horiuchi M, Fukuoka Y. Influence of Age on Cardiorespiratory Kinetics During Sinusoidal Walking in Humans. Front Physiol 2018; 9:1191. [PMID: 30197604 PMCID: PMC6117427 DOI: 10.3389/fphys.2018.01191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/07/2018] [Indexed: 12/04/2022] Open
Abstract
We sought to determine the influence of age on cardiorespiratory kinetics during sinusoidal walking in two groups: 13 healthy young subjects (YG; 7 men and 6 women, age 21 ± 2 years) and 15 healthy elderly subjects (ELD; 9 men and 6 women, age 67 ± 5 years). A treadmill’s speed was sinusoidally changed between 3 and 6 km h-1 in the YG and between 3 and 5 km h-1 in the ELD during periods of 1, 2, 5, and 10 min, and in a stepwise manner. We compared the groups’ heart rate (HR), ventilation (V˙E), and gas exchange (CO2 output (V˙CO2) and O2 uptake (V˙O2)) responses. We determined the phase shift (PS) and the normalized amplitude (Amp) ratio of these kinetics in relation to the sinusoidal change in walking speed in response to the magnitude from the maximum to minimum speeds as revealed by a Fourier analysis in all cardiorespiratory variables. Both the Amp ratio and PS in the V˙E, V˙CO2, and V˙O2 responses were very similar between the ELD and YG, and being independent of the periods of sinusoidal oscillations. In marked contrast, the PS of the HR kinetics was significantly slowed in the ELD compared to the YG. The Amp ratio of HR was not related to the covariance variation of HR (CVHR) at standing rest in the ELD. The HR kinetics during sinusoidal walking may not be attributable to parasympathetic nerve activity into the heart in the ELD. The slope of the Amp of V˙E related to the Amp of V˙CO2 (V˙E/V˙CO2 slope) was steeper in the ELD (0.0258) compared to the YG (0.0132), suggesting that exercise hyperpnea could be greatly induced during walking in the ELD. These findings suggest that aging influences the alterations of autonomic nervous system-dependent slower HR kinetics and exercise hyperpnea during walking in the ELD.
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Affiliation(s)
- Naoyuki Ebine
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
| | | | - Yuki Miyake
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
| | - Tatsuya Hojo
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
| | - Daijiro Abe
- Center for Health and Sports Science, Kyushu Sangyo University, Fukuoka, Japan
| | - Masahiro Horiuchi
- Division of Human Environmental Science, Mount Fuji Research Institute, Fujiyoshida, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Science, Doshisha University, Kyoto, Japan
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11
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Ebine N, Aoki T, Itoh M, Fukuoka Y. Differential kinetics of the cardiac, ventilatory, and gas exchange variables during walking under moderate hypoxia. PLoS One 2018; 13:e0200186. [PMID: 30044809 PMCID: PMC6059434 DOI: 10.1371/journal.pone.0200186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 06/21/2018] [Indexed: 11/19/2022] Open
Abstract
We investigated the effects of moderate hypoxia (FiO2 = 15%) on different kinetics between pulmonary ventilation ( V˙E) and heart rate (HR) during treadmill walking. Breath-by-breath V˙E, oxygen uptake ( V˙O2), carbon dioxide output ( V˙CO2), and HR were measured in 13 healthy young adults. The treadmill speed was sinusoidally changed from 3 to 6 km·h-1 with four oscillation periods of 1, 2, 5, and 10 min. The amplitude (Amp), phase shift (PS) and mean values of these kinetics were obtained by harmonic analysis. The mean values of all of these responses during walking at a sinusoidally changing speed became greater under hypoxia compared to normoxia (FiO2 = 21%), indicating that moderate hypoxia could achieve an increased energy expenditure (increased V˙O2 and V˙CO2) and hyperventilation. The Amp values of the V˙E, V˙O2, and V˙CO2 kinetics were not significantly different between normoxia and hypoxia at most periods, although a significantly smaller Amp of the HR was observed at faster oscillation periods (1 or 2 min).The PS of the HR was significantly greater under hypoxia than normoxia at the 2, 5, and 10 min periods, whereas the PS of the V˙E, V˙O2, and V˙CO2 responses was not significantly different between normoxia and hypoxia at any period. These findings suggest that the lesser changes in Amp and PS in ventilatory and gas exchange kinetics during walking at a sinusoidally changing speed were remarkably different from a deceleration in HR kinetics under moderate hypoxia.
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Affiliation(s)
- Naoyuki Ebine
- Faculty of Health and Sports Sciences, Doshisha University, Tatara, Kyotanabe, Kyoto, Japan
| | - Tomoko Aoki
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Higashiku, Kumamoto, Japan
| | - Masahiro Itoh
- Department of Physiology, Kumamoto University Graduate School of Life Sciences, Chyoku, Kumamoto, Japan
| | - Yoshiyuki Fukuoka
- Faculty of Health and Sports Sciences, Doshisha University, Tatara, Kyotanabe, Kyoto, Japan
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Higashiku, Kumamoto, Japan
- * E-mail:
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Drescher U, Koschate J, Hoffmann U, Schneider S, Werner A. Effect of acute ambient temperature exposure on cardio-pulmonary and respiratory kinetics in men. Int J Hyperthermia 2017; 34:442-454. [DOI: 10.1080/02656736.2017.1354402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Uwe Drescher
- Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany
| | - Jessica Koschate
- Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany
| | - Uwe Hoffmann
- Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany
| | - Stefan Schneider
- Institute of Movement and Neurosciences, German Sport University Cologne, Cologne, Germany
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore, Australia
| | - Andreas Werner
- Center for Space Medicine and Extreme Environments, Institute for Physiology, Charité University Medicine, Berlin, Germany
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Drescher U, Koschate J, Schiffer T, Schneider S, Hoffmann U. Analysis of heart rate and oxygen uptake kinetics studied by two different pseudo-random binary sequence work rate amplitudes. Respir Physiol Neurobiol 2017; 240:70-80. [DOI: 10.1016/j.resp.2017.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 03/03/2017] [Accepted: 03/04/2017] [Indexed: 10/20/2022]
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