Levels of tocopherol (T) in plasma and red blood cells (RBC) are assumed to be modulated by exercise. The mechanisms involved remain to be established. We examined the influence of different running bouts on the content of AT in RBC (TRBC), the oncentration in plasma (Tplasma), and their relationship with lipolysis, as indicated by changes () in plasma glycerol concentration ([glycerol]). Eleven healthy runners [mean (SD) age 35 (9) years, height 177.3 (7.6) cm, body mass 69.6 (9.4) kg, and peak oxygen consumption, VO2peak, 57.8 (4.8) ml.kg-1.min-1] performed an incremental treadmill test [duration 17 (2) min, peak velocity, vpeak 4.8 (0.4) m.s-1], a training run [173 (12) min, 57 (4)% vpeak] and a marathon [197 (24) min, 75 (5)% vpeak]. Before (pre) and after (post) each run, haematological and lipid parameters, TRBC and TPlasma were determined. Haemoconcentration was observed after each run. [glycerol] was +0.10 (0.10) mmol.l-1, +0.40 (0.14) mmol.l-1 and +0.51(0.15) mmol.l-1 in the treadmill test, training run and marathon, respectively. When corrected for haemoconcentration, values of Tplasma decreased [-5.4 (7.5)%, P<0.05] in the treadmill test, were unchanged [+0.7 (8.7)%] in the training run and increased [+7.8 (8.3)%, P<0.05] in the marathon. TRBC decreased [pre vs post: 22.7 (3.2) nmol.g haemoglobin-1 (nmol.g Hb-1) vs 18.9 (3.8) nmol.g Hb-1, P<0.05] in the treadmill test and was not significantly changed in either the training run [20.8 (1.9) nmol.g Hb-1 vs 19.1 (3.0) nmol.g Hb-1] or the marathon [21.6 (2.9) nmol.g Hb-1 vs 23.4 (2.7) nmol.g Hb-1]. TRBC and Tplasma were positively related to [glycerol]. The reduction in TRBC and Tplasma after short-lasting heavy exercise indicates the consumption of T, whereas the association between T and [glycerol] suggests mobilisation of T, especially in long-lasting exercises. However, although T appears to be influenced by exercise, the results suggest a well-balanced regulation of T during exercise resulting in small, and only in part, significant T in blood.
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