Conclusion: Results from university distance runners and untrained university students support the classic observation that SV plateaus at about 40% of maximal oxygen consumption despite increasing intensity of exercise.
Supportive relationships.
All other answers are negative and unhealthy
A tumor is an abnormal mass of tissue, which doesn't necessarily mean that you have cancer. Tumors can be benign, not cancerous, or they can be malignant, pre-cancerous. Another name for a tumor is a neoplasm.