Cano M.1, Ibacache P.2,3, Miranda C.3, Rojas J.C.2
1Universidad de Chile, Departamento de Kinesiología, Santiago, Chile, 2Universidad de las Américas, Departamento de Morfología y Función, Viña del Mar, Chile, 3Universidad Andrés Bello, Carrera de Kinesiología, Viña del Mar, Chile
Background: Obesity as became a major health problem worldwide. Whatever the health condition of a patient with obesity being seen in physical therapy setting, the prescription of a physical training program to improve the cardiorespiratory fitness should be one of the therapeutic goals of the treatment. To do so, is mandatory conduct an assessment of cardiorespiratory fitness which gold standard (VO2 peak) is expensive and cannot be done in primary care settings.
Purpose: To propose a method of estimating cardiorespiratory fitness (CRF) for adults patients with obesity that can be applied massively in primary care settings and using low cost equipment using 2 minutes step in place test, hand grip strength and inspiratory muscle strength.
Methods: 63 evaluations of cardiorespiratory fitness (CRF) of patients with obesity (mean age 36 years, 90% women) were performed. CRF was determined by stepwise protocol in cycle ergometer Monark 915 E (20-25 Watts increments every 2 min) until the stopping criteria (Respiratory Quotient ≥1.1 or modified perception rate of exertion > 7 point), with a Cortex Metalyzer 3b metabolic chart. The hand grip strength (HGS) was measured with a dynamometer Dynatron (using the EUROFIT protocol), considering the mean value between right and left sides. The inspiratory muscle strength (maximum inspiratory pressure) was evaluated with Powerbreathe K5, recording the highest value between three test. The 2 minutes step in place test (2MSIPT) was done according to the protocol described by Vaquero-Cristobal, recording the maximum number of steps taken by each patient. The results were analysed using SPSS 21.0 statistical software with a linear regression method.
Results: Subjects had a mean relative VO2 peak 22.2 ± 4.1 ml / kg / min (4.6 ± 1.9 L / min), a mean hand grip strength (HGS) 33 ± 11 kg. The maximum inspiratory muscle strength (MIMS) was 87 ± 25 cm H2O and performed 100 ± 14 steps in the 2MSIPT. There was a positive correlation determined by Spearman coefficient between VO2 absolute peak (L / min) and the number of steps made in the 2MSIPT (r = 0.375; p = 0.002), also with mean HGS (r = 0.624; p 0.001) and MIMS (r = 0.544; p 0.001).
With these results was proposed, using a linear regression method, the following formula to estimate the peak absolute oxygen consumption (r = 0.858; p 0.001).
VO2 peak (L / min) = -0.277 + (0.005 * number steps in 2MSIPT) + (0.037 * HGS) + (0.006 * MIMS).
Conclusion(s): A method was developed to reliably estimate CRF in adult subjects with obesity, using low-cost equipment, allowing its use in primary care settings.
Implications: With the proposed method there will be a simple way to assess objectively the cardiorespiratory fitness in adult patients with obesity in primary care clinical settings with minimum equipment.
Funding acknowledgements: This research was partially funded with resources of the Universidad de Chile and Universidad Andrés Bello.
Topic: Professional practice: other
Ethics approval: This research was approved by the Ethic Committee of Human Beings Research at Universidad de Chile (reg. number 149-2014).
All authors, affiliations and abstracts have been published as submitted.