Caffeine increases sweating sensitivity via changes in sudomotor activity during physical loading

J Med Food. 2011 Nov;14(11):1448-55. doi: 10.1089/jmf.2010.1534. Epub 2011 Sep 1.


We assessed the effect of caffeine on sudomotor activity and sweating sensitivity during physical loading. Both physiological responses could occur due to energy expenditure. Subjects were 13 athletically trained males (22.1 ± 3.7 years old, 174.2 ± 5.4 cm tall, and weighing 70.9 ± 4.6 kg, with maximal oxygen consumption [VO(2)max] of 53.6 ± 4.4 mL/kg/minute). The study involved a within-subject, random, crossover design. Tests were performed following the ingestion of 3 mg/kg caffeine. The physical loading involved running for 30 minutes at 60% VO(2)max (24.0 ± 0.5°C, 40 ± 3.0% relative humidity). Tympanic temperature (TYMP) was significantly higher in the caffeine-consuming group (Caffe-I) at pre-exercise (40 minutes after caffeine intake and immediately before running) (P<.05). Mean body temperature (mT(b)) was significantly higher in the Caffe-I group at pre- and post-exercise (30 min after start of running) (P<.05). Onset time of localized sweating was significantly shorter in the Caffe-I group (P<.01), but localized sweat volume and active sweat gland output (per single gland) was significantly higher in the Caffe-I group (P<.001). Activated sweat gland density was significantly increased in the Caffe-I group on the abdomen and thigh (P<.01). In conclusion, caffeine ingestion caused not only increases in TYMP and mT(b) through thermogenesis, but also an increased sweating sensitivity via changes in sudomotor activity.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Body Temperature Regulation
  • Caffeine / pharmacology*
  • Cross-Over Studies
  • Dose-Response Relationship, Drug
  • Energy Metabolism
  • Humans
  • Male
  • Motor Activity / drug effects*
  • Oxygen Consumption
  • Physical Exertion / drug effects*
  • Sweat Glands
  • Sweating / drug effects*
  • Young Adult


  • Caffeine