If you’re a man taking care of your health, bravo. Men are far less inclined to seek health care information. If you are looking after a loved one and need to nudge him about his health, then this information is for you, too.

In this three-part series, we’ll look at the impact of age on men’s health in their 30s, 40s, and 50s. What changes should you be aware of and what can you do to alleviate some of the effects that aging can have on your body.

In your 30s

Even if your physiological peak was in your 20s, you will only have a slight decline in your 30s. Exercise at any age can delay and, in some cases, reverse the effects of aging on your muscles, heart, and brain. It is important to continue, or start, an appropriate exercise regimen. Aim for at least 30 minutes each day. Strengthen your core (chest, abdomen, and back), too, to ward off balance issues.

While your muscle mass may remain the same, your bone mass begins to decline in your 30s. To keep your bones strong, you may want to take a calcium supplement, especially if you are not consuming calcium-rich foods. Weight-bearing exercise, even walking, can also slow bone loss.

As your age increases, so does your risk of infertility. A man has a biological clock similar to a woman’s biological clock. However, most men are not aware of the impact that their age has on infertility. Some professionals feel the role of the male in infertility has been grossly overlooked. As a man ages, so does his sperm. There is a natural decrease in volume, mobility, and structure of the sperm.

Testicular cancer is more common in men in their 30s. Know the warning signs and consult your doctor if you notice: a testicular lump; a feeling of heaviness in your scrotum; a dull ache in the groin; pain in the testicles or scrotum; breast tenderness or enlargement; overall fatigue. Of course, if you have a family history of testicular cancer, be even more vigilant.

Be aware that though less likely, prostate problems can begin in your 30s. If detected early, prostate cancer has a very high cure rate, so know the symptoms and talk to your doctor if you experience: dull pain in your lower abdomen, frequent or painful urination, low urine flow, blood in your urine or ejaculate, painful ejaculation, or persistent bone pain.

In your 30s, it’s a good idea to visit your doctor, even if it’s just to get some baseline readings. You will be better able track any changes that you notice. Cholesterol, body fat, and blood pressure all tend to rise in your 30s, as well. An annual visit will allow you and your doctor to monitor any changes and catch potential problems early.