The effects of acute exercise and high lactate levels on 35% CO2 challenge in healthy volunteers.
OBJECTIVE
To test the possible antipanic effects of acute exercise in healthy volunteers exposed to an inhalation of 35% CO2 challenge.


METHODS
Twenty healthy subjects in a randomized separate group design, performed exercise in a bicycle ergometer reaching >6 mm of blood lactate and a control condition of minimal activity in the same fashion with no lactate elevation. Immediately afterwards an inhalation of a vital capacity using a mixture of 35% CO2/65% O2 through a mask was given on both conditions.


RESULTS
Subjects under the exercise condition reported less panic symptoms than controls after a CO2 challenge on the diagnostic statistical manual-IV (DSM-IV) Panic Symptom List but no difference on the Visual Analogue Anxiety Scale.


CONCLUSIONS
Subjects under the exertion condition had lactate levels comparable with those of lactate infusions but an inhibitory rather than accumulative effect was seen when combined with a CO2 challenge.
D000328:Adult; D002245:Carbon Dioxide; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D007773:Lactates / Q000097:blood*; D008297:Male; D010200:Panic; D014797:Vital Capacity
D007773:Lactates; D002245:Carbon Dioxide