Exercise intervention does not reduce the likelihood of VO₂max underestimation in older adults with hypertension

ABSTRACT

The present study aimed to investigate whether training status would influence the capacity of a verification phase (VER) to confirm maximal oxygen uptake (VO₂max) of a previous graded exercise test (GXT) in individuals with hypertension. Twelve older adults with hypertension (8 women) were recruited. Using a within-subject design, participants performed a treadmill GXT to exhaustion followed by a multistage VER both before and after a 12-wkcombined exercise training programme. Individual VO₂max, respiratory exchange ratio (RER), maximal heart rate (HR_max), and rating of perceived exertion (RPE) were measured during both GXT and VER tests. Absolute and relative VO₂max values were higher in VER than in GXT at baseline, but only absolute VO₂max differed between bouts post-intervention (all p < 0.05). Individual VO₂max comparisons revealed that 75% of the participants (9/12) achieved a VO_2max value that was ≥3% during VER both before (range: +4.9% to +21%) and after the intervention (range: +3.4% to +18.8%), whereas 91.7% (11/12) of the tests would have been validated as a maximal effort if the classic criteria were employed. A 12-wk combined training intervention could not improve the capacity of older adults with hypertension to achieve VO₂max during a GXT, as assessed by VER.

KEYWORDS:

• Exercise testing
• verification phase
• oxygen consumption
• blood pressure

Highlights

1. A training intervention did not improve the participants’ capacity to achieve their VO₂max during GXT.

2. That is, irrespective of training status, VO₂max was underestimated in a large proportion of these individuals during GXT both at baseline and after the intervention.

3. As such, our results raise questions about the validity of VO₂max measured in the population investigated and support the use of a verification phase to confirm VO₂max attainment during GXT.

Acknowledgments

The authors are thankful for the administrative and funding support provided by the National Institute of Science and Technology for Health Technology Assessment (IATS/HCPA), Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil. E. N. W. was supported by the Brazilian Education Ministry Foundation CAPES (PNPD), whereas C.L.A was supported by the Brazilian National Council for Scientific and Technological Development (CNPq; conselho nacional de desenvolvimento científico e tecnológico.

Availability of data and material

Data from the present study will be made available upon request to the corresponding author.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The HAEL Study or involved personnel have been funded by CNPq, grant number 429849/2016-8 (Conselho Nacional de Desenvolvimento Científico e Tecnológico), FAPERGS (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul), CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), and FIPE (Fundo de Incentivo à Pesquisa e Eventos, Hospital de Clinicas de Porto Alegre).