Question
What is the maximum stress that a human spinal cord can withstand during lifting loads?
What is the advisable weight for a normal human being to lift during standing posture?

Answer
The maximum stress load has more to do with the vertebra surrounding the spinal cord rather than the spinal cord itself.  Since everyone has a different physical history, the load-bearing weight of the vertebra will differ also.  In addition, the age, size, and gender of the person is a factor that would have to be considered.  For example, an 18 year old male weighing 200 lbs. can typically tolerate more stress on the vertebra than a 65 year old woman weighing 120 lbs.

Regarding the standing lift, it depends on the exercise or method of lifting.  Overall, it is advisable to begin with lifting between 40-60% of your bodyweight and increase the amount as muscle strength and support allow.

Thank you for your question, Viji.  I hope that my answer was helpful.