Integra

Introduction
L-malate is an important intermediate on the process of metabolism; it plays an important role in generating
mitochondria ATP both under aerobic and hypoxic condition. It is easy to be absorbed and come into mitochondrion
through cell membrane and promote to produce energy in mitochondrion. The purpose of this investigation is to probe
into the different influence malate ingestion on blood lactate and glucose kinetics during aerobic exercise athletes.

Methods
20 male endurance-trained cyclists were divided three groups: contrast group (A), oligosaccharide solution group (G),
and malate plus oligosaccharide solution group (M). The nutrient solution is placebo for A group, 500mloligosaccharide
solution for G group and 3g-malate plus oligosaccharide solution for M group. Each subject performed
incremental cycling to exhaust to determine the VO2max. Arterialize blood was sampled for lactate determination at
rest, immediately after exercise, and at 3,5,7,12, 20, 30min post-exercise. Another test was carried out after 2days.
Subjects completed 45min cycle ergometer exercise at 60% VO2max. During cycling, 40ml blood sample was collected
at the time of 0, 15, 30, and 45min for blood glucose and blood lactate determinations. Venous blood was sampled
before and after exercise, and the blood serum was centrifuged for GOT and GPT activity.
Results
Comparisons between mean values for cycling time to exhaust are illustrated in Table 1. G2 and M2 groups had longer
time compared with G1 and M1. There were no significant difference between each group on VO2max and HRmax.

Discussion/ Conclusions
The results showed that:
1 The athletes supplied with oligosaccharide solution and malate plus oligosaccharide solution performed the cycling
to exhausted for a longer time;
2 Malate plus oligosaccharide solution have good effect on maintaining a higher blood glucose concentration during
exercise, increasing blood lactate removal rate;
3 Malate plus oligosaccharide solution has good effect on keeping decreased level of serum GOT and GPT activities
after exercise.
We can conclude that supplement of malate plus oligosaccharide can accelerate the lactate removal after exhausted
cycling, keep a higher blood glucose concentration during 45 min cycling exercise, and decrease the GOT and GPT
activities after exercise.

References
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