Aim: This study investigated whether markers related to type 1 diabetes (T1D) influence cardiopulmonary exercise (CPX) test performance in a group of world class road cyclists with T1D.
Methods: Fifteen elite male road cyclists with T1D (age 27±4 years, T1D duration 11±5 years, BMI 21.6±1.5 kg·min-2, HbA1c 6.8±0.6%) performed a ramped (10 W per min) CPX test to exhaustion. Adjusted stepwise linear regression analysis was performed to investigate relationships between markers of T1D control and absolute maximum markers of performance, maximum oxygen consumption (V O2max), maximum power output (Pmax) and maximum heart rate (HRmax). Associations between submaximal CPX parameters and V O2max,Pmax and HRmax were also investigated.
Results: Starting-CPX blood glucose (BG), post-CPX BG, ΔBG, T1D duration, HbA1c and BMI were not associated with V O2max (r2=0.51, P=0.32) and Pmax (r2=0.48, P=0.37) during CPX testing. However, HRmax was associated with T1D duration (r2=0.31, P=0.03). CO2 expiration at the lactate turn point 2 (V CO2LTP2) and power at the heart rate turn point (PHRTP) were associated with V O2max (r2=0.87, P<0.0001). These results were also associated when adjusted for T1D parameters (r2=0.95, p=0.002). Pmax was solely associated with V O2HRTP (r2=0.71, P<0.0001). Also, this association remained significant when adjusted for T1D parameters (r2=0.86, P=0.03).HRmax was associated with ventilation at the LTP2 (VELTP2), LactateLTP1, VCO2LTP2 and PLTP2 (r2=0.91, P=0.002). When this result was adjusted for T1D parameters the association was significant (r2=0.93, P=0.05).
Conclusion: This is the first dataset presenting CPX data from a world class cycle team with T1D. The study shows that not all markers of maximum physiological performance are influenced by T1D, solely HRmax by T1D duration. Yet, maximum performance is dependent on several submaximal cardiopulmonary markers of performance.
M.L. Eckstein: Research Support; Self; Novo Nordisk A/S. O. Moser: Research Support; Self; Abbott, Dexcom, Inc., Novo Nordisk A/S. O. McCarthy: None. S.N. Scott: None. M. Riddell: Advisory Panel; Self; Xeris Pharmaceuticals, Inc. Consultant; Self; Lilly Diabetes. Research Support; Self; Dexcom, Inc., Insulet Corporation, Novo Nordisk Inc., Sanofi. Speaker’s Bureau; Self; Medtronic MiniMed, Inc., OmniPod. Stock/Shareholder; Self; Zucara Therapeutics Inc. F.Y. Fontana: None. K. Skroce: None. M.P. Christiansen: Research Support; Self; Abbott, Biolinq, Dexcom, Inc., Eli Lilly and Company, Janssen Pharmaceuticals, Inc., Medtronic MiniMed, Inc., Novo Nordisk A/S, Sanofi-Aventis, Xeris Pharmaceuticals, Inc. L. Festa: None. M. Fisher: Advisory Panel; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Mylan, NAPP Pharmaceuticals Limited, Novo Nordisk A/S. Speaker’s Bureau; Self; Eli Lilly and Company, Sanofi. C.A. Hayes: Other Relationship; Self; Novo Nordisk A/S. P. Southerland: Other Relationship; Self; Novo Nordisk Inc. C. Stettler: None. P.H. Lagrou: None. B.W. Bode: Consultant; Self; ADOCIA, Lexicon Pharmaceuticals, Inc., Novo Nordisk Inc. Research Support; Self; Becton, Dickinson and Company, Dexcom, Inc., Diasome Pharmaceuticals, Inc., Eli Lilly and Company, Eyenuk Inc., Insulet Corporation, National Institutes of Health, Novo Nordisk Inc., Sanofi Research & Development, Senseonics, Xeris Pharmaceuticals, Inc. Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Janssen Pharmaceuticals, Inc., Novo Nordisk Inc., Sanofi US, Senseonics. Stock/Shareholder; Self; AgaMatrix, Glytec, LLC. R.M. Bracken: None.
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