���ϳԹ���

You can do quite a bit. Although, there gets to be a point where you might be better off just buying a new bag and being done with it.

Therm-a-Rest Z-Lite

Z-Lite Closed Cell Sleeping Pad

For starters, make sure you’re well-dressed, head to toe. Midweight long underwear (REI Midweight MTS top, $35, and bottoms, $30; rei.com), plus gloves, hat, and warm socks (Smartwool Light Hikers, $15; smartwool.com). There’s nothing at all wrong with adding to that a fleece jacket or anything else. Insulation is insulation. The only caveat is not to over-stuff your sleeping bag so much, with you and all your clothing, that you press against the inner shell and compress the insulation.

Second, make sure you’re well-fed. Eating a candy bar or something similar just before bedtime (nothing with caffeine, obviously) will give you a few extra calories to keep warm with during the night.

The coldest spot is always the ground, so make sure you’re covered there. Double up on your pads. If you have a good inflatable pad such as a Therm-a-Rest Prolite 4 ($85; thermarest.com), supplement it with an inexpensive Ensolite (closed-cell foam) pad for $15 or $20.

Finally, you can add a liner to your bag. Kelty’s Fleece Sleeping Bag Liner ($45; kelty.com) will add about ten degrees to the low end of the bag’s comfort end.

Or, you could just go out and buy a North Face Cat’s Meow with Polarguard insulation and a 20-degree temperature rating for only $159 (thenorthface.com).

You’ve seen our picks for 2007 Gear of the Year, and now the entire
���ϳԹ��� Summer Buyer’s Guide is online. Check out this year’s more than 400 must-have gear items, including tents.