Backpacks can cause neck, shoulder, and back discomfort if not selected and worn properly. Here are some tips to follow to avoid problems:

Limit the load you carry to about 15% of your body weight. That's 22.5 pounds if you weigh 150 pounds. Many doctors recommend a maximum of 25 pounds, no matter how big you are.

Absorb force. Look for features like wide, padded shoulder straps, and air-filled cushions.

Distribute weight evenly. Wear shoulder straps over both shoulders. Slinging the straps over one shoulder increases strain and can cause you to lean to one side. Use waist belts to shift work to your trunk and hip.

Keep the load close. The further a load is away from your back, the more your back muscles have to work. Adjust straps to keep the pack snug against your back.

Position your pack between your shoulders and hips. Your backpack should hang just below the shoulders with the bottom resting in your low back curve. Never let it hang more than 4 inches below your waist.

Pack it to minimize weight load.

• Use multiple compartments.
• Arrange items so they don't shift around.
• Place heaviest items closest to your back.
• Use a wheeled backpack for heavy loads and long distances.

Look for well-designed models. The following packs provide good fit, comfort and are back-friendly:

Jansport Freefall $60 (sonomaoutfitters.com)
REI Bookpacker $35 (rei.com)
Super Padre $85-145 (toughtraveler.com)
Posture Pack $50 (posturepack.com)