Minute ventilation and heart rate relationship for estimation of the ventilatory compensation point at high altitude: a pilot study

Extreme Physiology & Medicine

Paolo Palange¹  Annalisa Cogo²  Paolo Onorati³  Alessandro M Ferrazza³  Mattia Internullo³  Gabriele Valli³ 

[1] Eleonora Lorillard Spencer Cenci Foundation, Piazzale Aldo Moro n. 5, Rome, 00185, Italy;Biomedical Sport Studies Center, University of Ferrara, Via Gramicia 35, Ferrara, 44123, Italy;Lung Function Unit, Department of Public Health and Infectious Diseases, University of Rome “La Sapienza”, viale Università 37, Rome, 00185, Italy

关键词: Heart rate;    Ventilation;    Exercise;    Ventilatory compensation point;    High altitude;   

Others  :  817394
DOI  :  10.1186/2046-7648-2-7

 received in 2012-06-19, accepted in 2013-01-11,  发布年份 2013

【 摘 要 】

Background

The ventilatory compensation point (VCP) is an exercise threshold which has been used in the design of training programs in sports medicine and rehabilitation. We recently demonstrated that changes in the slope of the minute ventilation to heart rate relationship (View MathML">) can be utilized for estimation of the VCP during incremental exercise at sea level (SL). We hypothesized that in hypoxic conditions, such as high altitude (HA), VCP can be also reliably estimated by View MathML">.

Methods

At SL and on immediate ascent to HA (5,050 m), six healthy subjects (42 ± 14 SD years) performed a maximal incremental exercise test on a cycle ergometer; O₂ uptake (View MathML">), CO₂ output (View MathML">), View MathML">, and HR were measured breath-by-breath. The View MathML"> method for VCP estimation was compared to the standard method using the ventilatory equivalent for CO₂ (View MathML">) and end-tidal PCO₂ (P_ETCO₂). The View MathML"> slope values below (S₁) and above (S₂) VCP were computed by linear regression analysis.

Results

A significant difference between S₁ and S₂ was observed, at SL and HA, for both the View MathML"> and View MathML"> methods for VCP estimation. A good agreement between the two methods (View MathML"> vs. View MathML">) was found for both environmental conditions; the mean difference ± 2 SD of View MathML"> at VCP (VCP-View MathML">) was −22 ± 112 ml/min at SL and 39 ± 81 ml/min at HA. The VCP-View MathML"> was significantly lower at HA compared to SL; in addition, S₁ and S₂ mean values were significantly higher at HA compared to SL.

Conclusion

At HA, VCP may be reliably estimated by the View MathML"> method.

【 授权许可】

   
2013 Valli et al.; licensee BioMed Central Ltd.

【 图 表 】

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