Validity of the Astrand-Ryhming nomogram for predicting maximal oxygen intake

Area of Science:

• Exercise Physiology
• Cardiorespiratory Fitness Assessment

Background:

• The Astrand-Ryhming nomogram is a widely used tool for estimating maximal oxygen uptake (VO2 max).
• Accurate VO2 max prediction is crucial for fitness assessment and exercise prescription.
• The influence of different age correction factors on nomogram validity requires further investigation.

Purpose of the Study:

• To evaluate the predictive validity of the Astrand-Ryhming nomogram for VO2 max using a cycle ergometer.
• To compare the accuracy of two sets of age correction factors (Astrand and von Dobeln) in VO2 max prediction.
• To determine the optimal age correction factors for use with the Astrand-Ryhming nomogram.

Main Methods:

• Submaximal cycle ergometer testing was performed on 40 male subjects.
• VO2 max was predicted using the Astrand-Ryhming nomogram with both Astrand and von Dobeln age correction factors.
• Predicted VO2 max values were compared to measured values, with statistical analysis of accuracy (SEE, r, mean difference).

Main Results:

• The Astrand age correction factors yielded a SEE of .42 L.min-1 (5.7 ml.kg-1.min-1) with high correlations (r = .76 and .83).
• No significant difference was found between measured and predicted VO2 max when using Astrand factors.
• The von Dobeln age correction factors resulted in a significantly lower predicted mean VO2 max, indicating underestimation.

Conclusions:

• The Astrand-Ryhming nomogram, when used with Astrand age correction factors, provides a valid estimation of VO2 max via cycle ergometry.
• Astrand age correction factors are recommended for accurate VO2 max prediction and fitness classification.
• The von Dobeln age correction factors may consistently underestimate VO2 max, limiting their utility in fitness assessment.