I'm 36 years old, healthy, smoker, doing a lot of sport activity. my ldl is 173.9, total cholesterol 261.4, hdl 68 and tg 98. am i at high risk?

Yes: Your LDL and cholestrol are higher than desired. While HDL and trig are good, smoking and high LDL put you at a higher risk of cardiovascular disease. First thing you should do is quit smoking. Depending on your family history and rest of health issues, your doctor may put you on a statin. It would be prudent to see your doctor about it. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.