Key result
Age and cardiorespiratory fitness did not limit pulmonary capillary network expansion during exercise, with similar DLCO-cardiac output slopes across young, old, and highly fit groups (P=0.388).
Why the study?
Does age and cardiorespiratory fitness affect the lung diffusing capacity response to incremental exercise in healthy humans?
Observational
Does age and cardiorespiratory fitness affect the lung diffusing capacity response to incremental exercise in healthy humans?
p-value: p=0.388
Despite age-associated deterioration in pulmonary circulation, expansion of the pulmonary capillary network does not become limited during high-intensity exercise in healthy individuals, regardless of age or cardiorespiratory fitness level.
Highly fit older adults maintain DLCO during heavy exercise; leaves open whether fitness preserves pulmonary function with aging.
Aging is associated with deterioration in the structure and function of the pulmonary circulation. We characterized the lung diffusing capacity for carbon monoxide (DL CO ), alveolar-capillary membrane conductance (Dm CO ), and pulmonary-capillary blood volume (Vc) response to discontinuous incremental exercise at 25, 50, 75, and 90% of peak work (W peak ) in four groups: 1) Young [27 ± 3 yr, maximal oxygen consumption (V̇o 2max ): 110 ± 18% age predicted]; 2) Young Highly Fit (27 ± 3 yr, V̇o 2max : 147 ± 8% age predicted); 3) Old (69 ± 5 yr, V̇o 2max : 116 ± 13% age predicted); and 4) Old Highly Fit (65 ± 5 yr, V̇o 2max : 162 ± 18% age predicted). At rest and at 90% W peak , DL CO , Dm CO , and Vc were decreased with age. At 90% W peak , DL CO , Dm CO , and Vc were greater in Old Highly Fit vs. Old adults. The slope of the DL CO -cardiac output (Q̇) relationship from rest to end exercise at 90% W peak was not different between Young, Young Highly Fit, Old, and Old Highly Fit (1.35 vs. 1.44 vs. 1.10 vs. 1.35 ml CO ·mmHg −1 ·liter blood −1 , P = 0.388), with no evidence of a plateau in this relationship during exercise; this was also true for Dm CO -Q̇ and Vc-Q̇. V̇o 2max was positively correlated with 1) DL CO , Dm CO , and Vc at rest; and 2) the rest to end exercise change in DL CO , Dm CO , and Vc. In conclusion, these data suggest that despite the age-associated deterioration in the structure and function of the pulmonary circulation, expansion of the pulmonary capillary network does not become limited during exercise in healthy individuals regardless of age or cardiorespiratory fitness level. NEW & NOTEWORTHY Healthy aging is a crucial area of research. This article details how differences in age and cardiorespiratory fitness level affect lung diffusing capacity, particularly during high-intensity exercise. We conclude that highly fit older adults do not experience a limit in lung diffusing capacity during high-intensity exercise. Interestingly, however, we found that highly fit older individuals demonstrate greater values of lung diffusing capacity during high-intensity exercise than their less fit age-matched counterparts.
No takes yet. Share an insight, caveat, or question.
Coffman et al. (2017) conducted an observational in Healthy humans. Age and cardiorespiratory fitness vs. Young and/or less fit individuals was evaluated on Slope of the DLCO-cardiac output relationship from rest to end exercise at 90% Wpeak (p=0.388). Age and cardiorespiratory fitness did not limit pulmonary capillary network expansion during exercise, with similar DLCO-cardiac output slopes across young, old, and highly fit groups (P=0.388).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: