A 23-year-old casual runner and a 45-year-old fitness runner rarely get the same injuries. As we age, the way our tissues absorb the impact of running shifts completely.

If you want to stay injury-free, it helps to understand the unique structural weak points of your age bracket. Here's where each group tends to break down.

Similar overall injury rates, very different locations.

The young runner's vulnerability: the knee and bone

Younger runners have an overall injury rate of about 45%. Because their bone remodelling and joint mechanics absorb massive amounts of shock at the knee, they're overwhelmingly prone to:

• Patellofemoral pain (runner's knee): irritation under or around the kneecap.
• Bone stress injuries: shin splints (medial tibial stress syndrome, or MTSS) and tibial stress fractures.

The masters runner's vulnerability: the calf and Achilles

Once you cross into the masters category, your overall injury rate climbs slightly to 49%, but where you get injured changes completely. As we age, our tendons become less compliant and our calf muscles absorb less energy. That shifts the load further down the leg, leaving masters runners highly susceptible to:

• Calf strains: accounting for nearly 10% of masters running injuries.
• Achilles tendinopathy: irritation of the thick tendon at the back of your ankle.
• Plantar fasciopathy: heel and arch pain.

Your action plan