As long as your BP is high enough that you can talk to me and stand without passing out I do not pay attention to the number

this

Just wondered what the med tent considers low blood pressure after an Ironman?

I'm down to 100/55 the day after a very tough 5 hour hill climb - from a normal 115/70 - and HR is up to 50 from a normal 43.

I've been interpreting low bp as low on electrolytes and liquid and wonder how others would interpret this.

thanks for your insight,

Actually the fastest folks come in dehydrated. Your current drink to discomfort setsbyounupnfor hyponatremia

Abstract
Objective It is purported that exercise-induced dehydration (EID), especially if =/> 2% bodyweight, impairs endurance performance (EP). Field research shows that athletes can achieve outstanding EP while dehydrated > 2% bodyweight. Using the meta-analytic procedure, this study compared the findings of laboratory-based studies that examined the impact of EID upon EP using either ecologically valid (EV) (time-trial exercise) or non-ecologically valid (NEV) (clamped-intensity exercise) exercise protocols.
Methods EP outcomes were put on the same scale and represent % changes in power output between euhydrated and dehydrated exercise tests. Random-effects model meta-regressions and weighted mean effect summaries, mixed-effects model analogue to the ANOVAs and magnitude-based effect statistics were used to delineate treatment effects.
Main results Fifteen research articles were included, producing 28 effect estimates, representing 122 subjects. Compared with euhydration, EID increased (0.09±2.60%, (p=0.9)) EP under time-trial exercise conditions, whereas it reduced it (1.91±1.53%, (p<0.05)) with NEV exercise protocols. Only with NEV exercise protocols did EID =/> 2% bodyweight impair EP (p=0.03).
Conclusions Evidence indicates that (1) EID </= 4% bodyweight is very unlikely to impair EP under real-world exercise conditions (time-trial type exercise) and; (2) under situations of fixed-exercise intensity, which may have some relevance for military and occupational settings, EID =/> 2% bodyweight is associated with a reduction in endurance capacity. The 2% bodyweight loss rule has been established from findings of studies using NEV exercise protocols and does not apply to out-of-doors exercise conditions. Athletes are therefore encouraged to drink according to thirst during exercise.

recent meta-analysis
http://bjsm.bmj.com/content/early/2012/07/03/bjsports-2012-090958.abstract?sid=b963241b-404b-41a5-a546-c81cef2723e9

Thanks!!

Great info - I've been trying to limit my weight loss to 2% - 3.5 lbs - and I've always suspected it is my fitness level not my electrolyte level that causes cramping late in races / late in long rides. I'll relax fluid intake to steady intake rather than to feeling full - maybe take in some more food - and see how that works. Feels like I'm often training at just below a threshold of cramping - and always racing there - not sure if that is normal for many?