Lighten up, and quit toting that heavy load

Backpacks are getting lighter. The growth of adventure racing and shorter, faster, more athletic backpacking has led to the widespread use of lighter materials and minimalist frame designs that give up nothing in strength and durability. With built-in hydration ports and plenty of pouches and zippered compartments, these featherweights prove that you can take it all with you. Even deep into the woods.

-- Roy M. Wallack

Speedy baggage

Gregory Advent Pro: On-the-go design for speed hikers and adventure racers.

Likes: Mesh, zippered pockets on the waistbelt allow instant access to energy bars and maps. Main storage compartment can be accessed from the top, the sides or the bottom. Bottom section is separated. Three external mesh pockets for storage. Lid pocket for light, delicate items. Hydration-bladder compatible. Cinch straps on chest straps allow you to carry water bottles, lights or other quick-grab items. Good space for a light day pack -- sizes from 2 pounds, 13 ounces, to 1 pound, 14 ounces.

Dislikes: Like most frameless one-day packs, it can fatigue your shoulders if stuffed too heavily. Hydration bladder is not included.

Price: $149. (800) 477-3420; www.gregorypacks.com.

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Air-conditioned weekender

Osprey Atmos 50: Mid-size, two- to three-day aluminum-framed pack with unique back ventilation.

Likes: Arched, mesh back panel reduces perspiration by putting several inches of space between your back and the pack. Hydration-bladder compatible. Quick energy-bar access from mesh, zip pockets on the waist belt. External tool-gear loops and stretchable rear pocket add storage. Sliding sternum strap allows a custom fit across chest. Removable lid and sleeping bag strap. Sizes from 2 pounds, 15 ounces to 3 pounds, 3 ounces. Note: The Aura, a female-specific version, debuts in May.

Dislikes: Hydration bladder not included.

Price: $199. (970) 564-5900. www.ospreypacks.com.

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Mid-size value

Kelty Illusion 3500: Economical, efficient pack built for three- to four-day trips.

Likes: Lots of organized storage, with five mesh pockets, a daisy chain (fabric loops) to clip on gear, an ice ax loop, a carry-all shovel pocket, internal load pocket, mesh water bottle pocket, and map pocket. Comfortable, padded straps. Hydration compatible. Weighs 3 pounds, 7 ounces.

Dislikes: No pockets on waistbelt. No hydration bladder included.

Price: $160. (800) 423-2320; www.kelty.com.

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Heavy-load lightener

Mountain Hardwear Maestro: Seven-day pack with a uniquely agile and fatigue-reducing design.

Likes: The innovative frame design, featuring a stiff chest harness and belt and a rigid aluminum collar and stays, props the load off your shoulders and onto rods anchored to your hipbelt. The pack stays stable and comfortable even at a fast pace because the rod’s bases pivot with your hips. The narrow profile allows a natural, unobstructed arm swing. Hydration-bladder compatible. Sizes from 5 pounds, 4 ounces, to 6 pounds, 4 ounces.

Dislikes: No quick access to items at the bottom of the top-loading main compartment due to lack of zippers. No pockets on waistbelt. Hydration bladder not included.

Price: $369. (800) 953-8375; www.mountainhardware.com.