TY - JOUR
T1 - Priming exercise accelerates oxygen uptake kinetics during high-intensity cycle exercise in middle-aged individuals with type 2 diabetes
AU - Rocha, Joel
AU - Gildea, Norita
AU - O'Shea, Donal
AU - Green, Simon
AU - Egaña, Mikel
N1 - Copyright:
© 2022 Rocha, Gildea, O’Shea, Green and Egaña. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Data availability statement:
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.
PY - 2022/11/18
Y1 - 2022/11/18
N2 -
Background: The primary phase time constant of pulmonary oxygen uptake kinetics (
V
·
O
2
τ
p) during submaximal efforts is longer in middle-aged people with type 2 diabetes (T2D), partly due to limitations in oxygen supply to active muscles. This study examined if a high-intensity "priming" exercise (PE) would speed
V
·
O
2
τ
p during a subsequent high-intensity cycling exercise in T2D due to enhanced oxygen delivery.
Methods: Eleven (4 women) middle-aged individuals with type 2 diabetes and 11 (4 women) non-diabetic controls completed four separate cycling bouts each starting at an 'unloaded' baseline of 10 W and transitioning to a high-intensity constant-load. Two of the four cycling bouts were preceded by priming exercise. The dynamics of pulmonary
V
·
O
2
and muscle deoxygenation (i.e. deoxygenated haemoglobin and myoglobin concentration [HHb + Mb]), were calculated from breath-by-breath and near-infrared spectroscopy data at the vastus lateralis, respectively.
Results: At baseline
V
·
O
2
τ
p, was slower (
p < 0.001) in the type 2 diabetes group (48 ± 6 s) compared to the control group (34 ± 2 s) but priming exercise significantly reduced
V
·
O
2
τ
p (
p < 0.001) in type 2 diabetes (32 ± 6 s) so that post priming exercise it was not different compared with controls (34 ± 3 s). Priming exercise reduced the amplitude of the
V
·
O
2
slow component (A
s) in both groups (type 2 diabetes: 0.26 ± 0.11 to 0.16 ± 0.07 L/min; control: 0.33 ± 0.13 to 0.25 ± 0.14 L/min,
p < 0.001), while [HHb + Mb] kinetics remained unchanged.
Conclusion: These results suggest that in middle-aged men and women with T2D, PE speeds
V
·
O
2
τ
p likely by a better matching of O
2 delivery to utilisation and reduces the
V
·
O
2
A
s during a subsequent high-intensity exercise.
AB -
Background: The primary phase time constant of pulmonary oxygen uptake kinetics (
V
·
O
2
τ
p) during submaximal efforts is longer in middle-aged people with type 2 diabetes (T2D), partly due to limitations in oxygen supply to active muscles. This study examined if a high-intensity "priming" exercise (PE) would speed
V
·
O
2
τ
p during a subsequent high-intensity cycling exercise in T2D due to enhanced oxygen delivery.
Methods: Eleven (4 women) middle-aged individuals with type 2 diabetes and 11 (4 women) non-diabetic controls completed four separate cycling bouts each starting at an 'unloaded' baseline of 10 W and transitioning to a high-intensity constant-load. Two of the four cycling bouts were preceded by priming exercise. The dynamics of pulmonary
V
·
O
2
and muscle deoxygenation (i.e. deoxygenated haemoglobin and myoglobin concentration [HHb + Mb]), were calculated from breath-by-breath and near-infrared spectroscopy data at the vastus lateralis, respectively.
Results: At baseline
V
·
O
2
τ
p, was slower (
p < 0.001) in the type 2 diabetes group (48 ± 6 s) compared to the control group (34 ± 2 s) but priming exercise significantly reduced
V
·
O
2
τ
p (
p < 0.001) in type 2 diabetes (32 ± 6 s) so that post priming exercise it was not different compared with controls (34 ± 3 s). Priming exercise reduced the amplitude of the
V
·
O
2
slow component (A
s) in both groups (type 2 diabetes: 0.26 ± 0.11 to 0.16 ± 0.07 L/min; control: 0.33 ± 0.13 to 0.25 ± 0.14 L/min,
p < 0.001), while [HHb + Mb] kinetics remained unchanged.
Conclusion: These results suggest that in middle-aged men and women with T2D, PE speeds
V
·
O
2
τ
p likely by a better matching of O
2 delivery to utilisation and reduces the
V
·
O
2
A
s during a subsequent high-intensity exercise.
U2 - 10.3389/fphys.2022.1006993
DO - 10.3389/fphys.2022.1006993
M3 - Article
C2 - 36505082
SN - 1664-042X
VL - 13
JO - Frontiers in Physiology
JF - Frontiers in Physiology
M1 - 1006993
ER -
