Hi, Thanks for using this forum. Firstly the blood in semen is surely not from hernia. It is related to the strenuous workout and this is usually seen in young adults. Symptom can be quite alarming however it does not signify any serious medical problem. The cause can be due to any trauma to the testis or prostrate during the workout. This causes small blood vessels to bleed and present as blood in the semen. Other possible causes can be Urinary tract infection , inflammation of prostrate, sexually transmitted disease such as gonorrhea, or any injury to the urinary bladder or urethra. Usually such episodes of bleeding resolve spontaneously however further evaluation by a doctor would be required incase of persistent bleeding. The soreness of the public region also points towards underlying trauma or infection. Odor is another symptom for underlying infection. You should avoid strenuous workout for now and follow up closely with the color of semen discharge. Further investigations such as urine test and ultrasound would be required if symptoms still prevail. Contact your doctor in this case. Regards