@article{WiesnerBirkenfeldEngelietal.2010,
  author    = {Wiesner, Stefan and Birkenfeld, Andreas L. and Engeli, Stefan and Haufe, Sven and Brechtel, Lars and Wein, J. and Hermsdorf, Mario and Karnahl, Brita and Berlan, Michel and Lafontan, Max and Sweep, Fred C. G. J. and Luft, Friedrich C. and Jordan, Jens},
  title     = {Neurohumoral and metabolic response to exercise in water},
  issn      = {0018-5043},
  doi       = {10.1055/s-0030-1248250},
  year      = {2010},
  abstract  = {Atrial natriuretic peptide (ANP) stimulates lipid mobilization and lipid oxidation in humans. The mechanism appears to promote lipid mobilization during exercise. We tested the hypothesis that water immersion augments exercise- induced ANP release and that the change in ANP availability is associated with increased lipid mobilization and lipid oxidation. In an open randomized and cross-over fashion we studied 17 men (age 31 +/- 3.6 years; body mass index 24 +/- 1.7 kg/m(2); body fat 17 +/- 6.7\%) on no medication. Subjects underwent two incremental exercise tests on a bicycle ergometer. One test was conducted on land and the other test during immersion in water up to the xiphoid process. In a subset (n = 7), we obtained electromyography recordings in the left leg. We monitored gas exchange, blood pressure, and heart rate. In addition, we obtained blood samples towards the end of each exercise step to determine ANP, norepinephrine, epinephrine, lactate, free fatty acids, insulin, and glucose concentrations. Heart rate, systolic blood pressure, and oxygen consumption at the anaerobic threshold and during peak exercise were similar on land and with exercise in water. The respiratory quotient was mildly reduced when subjects exercised in water. Glucose and lactate measurements were decreased whereas free fatty acid concentrations were increased with exercise in water. Water immersion attenuated epinephrine and norepinephrine and augmented ANP release during exercise. Even though water immersion blunts exercise-induced sympathoadrenal activation, lipid mobilization and lipid oxidation rate are maintained or even improved. The response may be explained by augmented ANP release.},
  language  = {en}
}
@article{LehnStefanPeterMachannetal.2022,
  author    = {Lehn-Stefan, Angela and Peter, Andreas and Machann, J{\"u}rgen and Schick, Fritz and Randrianarisoa, Elko and Heni, Martin and Wagner, Robert and Birkenfeld, Andreas L. and Fritsche, Andreas and Schulze, Matthias Bernd and Stefan, Norbert and Kantartzis, Konstantinos},
  title     = {Impaired metabolic health and low cardiorespiratory fitness independently associate with subclinical atherosclerosis in obesity},
  series = {The journal of clinical endocrinology \& metabolism},
  volume    = {107},
  journal   = {The journal of clinical endocrinology \& metabolism},
  number    = {6},
  publisher = {Endocrine Society},
  address   = {Washington},
  issn      = {0021-972X},
  doi       = {10.1210/clinem/dgac091},
  pages     = {E2417 -- E2424},
  year      = {2022},
  abstract  = {Context For a given body mass index (BMI), both impaired metabolic health (MH) and reduced cardiorespiratory fitness (CRF) associate with increased risk of cardiovascular disease (CVD). Objective It remains unknown whether both risk phenotypes relate to CVD independently of each other, and whether these relationships differ in normal weight, overweight, and obese subjects. Methods Data from 421 participants from the Tubingen Diabetes Family Study, who had measurements of anthropometrics, metabolic parameters, CRF (maximal aerobic capacity [VO2max]) and carotid intima-media thickness (cIMT), an early marker of atherosclerosis, were analyzed. Subjects were divided by BMI and MH status into 6 phenotypes. Results In univariate analyses, older age, increased BMI, and a metabolic risk profile correlated positively, while insulin sensitivity and VO2max negatively with cIMT. In multivariable analyses in obese subjects, older age, male sex, lower VO2max (std. ss -0.21, P = 0.002) and impaired MH (std. ss 0.13, P = 0.02) were independent determinants of increased cIMT. After adjustment for age and sex, subjects with metabolically healthy obesity (MHO) had higher cIMT than subjects with metabolically healthy normal weight (MHNW; 0.59 +/- 0.009 vs 0.52 +/- 0.01 mm; P < 0.05). When VO2max was additionally included in this model, the difference in cIMT between MHO and MHNW groups became statistically nonsignificant (0.58 +/- 0.009 vs 0.56 +/- 0.02 mm; P > 0.05). Conclusion These data suggest that impaired MH and low CRF independently determine increased cIMT in obese subjects and that low CRF may explain part of the increased CVD risk observed in MHO compared with MHNW.},
  language  = {en}
}