100 things you need to know about walking, running, hiking & trekking: there's no better exercise for body, mind and soul. Here's all the fitness, fashion and gear you'll need to put your best foot forward wherever you go

Whether you're walking around the block, running on the beach, hiking a woodland trail or trekking through a national park, putting one foot in front of the other at a brisk pace mixes health benefits with the pure pleasure of movement.

Walking is as basic an exercise as it comes. You can pump up your program by going faster or longer, wearing a weighted vest or moving up and down more hills. To help you on your way, we've gathered a panel of experts to devise a comprehensive list of tips, techniques and gear picks for fabulous fresh-air fitness.

1 Get off the flats and into the hills. Walking uphill makes you stronger and is especially great for your butt, thighs, and abs. If a hill is too steep for comfort, zigzag up or down.

2 Each step puts up to 1.5 times your body weight on your feet, which are shock absorbers that bear 60 tons of pressure every mile you travel.

3 Find your stride length: Standing with your feet t together, lean forward from your ankles until you are forced to take a step. Where your heel lands is your proper stride length when walking for fitness.

4 The more fit you are, the harder it is to reach your target heart rate.

5 Strengthen ankles and calves for more efficient movement and less chance of injury. Try hopping or skipping for 30 seconds between run or walk intervals.

6 Intervals increase walking or running endurance. Alternate 3 to 5 minutes walking at a moderate pace with 1 to 2 minutes at a faster, more intense pace. Repeat at least 5 to 7 times.

7 Wear merino wool or synthetic blend socks to prevent blisters. Avoid cotton; it traps sweat.

8 Keep water cool by filling the reservoir of your hydration pack half full with water. Freeze and then fill with water just before you start your hike.

9 Three blasts of a whistle is the universal signal for help.

10 A 145-pound woman walking briskly (4 mph) burns 82 calories every 15 minutes.

11 Walk, run or hike to maintain your weight. Sedentary non-dieters can gain nearly 5 pounds a year, according to a report in the Archives of Internal Medicine. To lose weight, walk 45 to 60 minutes a day briskly.

12 Always walk or run facing traffic.

13 Always carry a compass when hiking, even if you've gone high-tech and have a GPS (global positioning system).

14 plank (to strengthen arms, shoulders, chest, thighs, buttocks) Kneel on the ground, wrists aligned with the shoulders, arms extended, fingers facing forward. Extend one leg behind you at a time, and balance on the balls of your feet. Lower your hips and balance the torso by pulling your abs in so your body forms one straight line from head to heels (shown). Hold for 30 seconds, progressing 1 minute, without letting your belly sag or upper back cave in.

15 Try on walking or running shoes after you've exercised and your feet are swollen. Wear the socks you use for the activity. Your walking or running shoe should be a half-inch longer than the length of your longest toe.

16 Increase your walking speed by bending your elbows to a go-degree angle and driving your elbows backward as if hitting a punching bag in opposition to your legs. Simply taking a longer stride won't do it.

17 Walk with a comfortable stride. Strike the ground with your heel, then roll through the arches, pushing off the ball of your foot. Contract your abs, hips pointing forward. Swing your arms in opposition to your legs forward and back, not side to side.

18 To stay healthy, walk 230 minutes a day at a comfortable pace. If you can't find a 30-minute span to exercise each day, try 15 minutes in the morning and 15 minutes after work.

19 Your shoes are too stiff if your feet slap down rather than roll through the ball of your foot as you walk.

20 To improve agility and balance for leaping across creeks, crevices and other obstacles on the trail, stand on one foot, jump straight up, repeat 10 times, then switch legs. Or prepare by leaping from one foot to the other.

21 Take little steps, not big ones, for a long hike to conserve your strength; if you're panting, you're going too fast.

22 If you've taken off more than one month from exercising, give yourself at least four weeks to regain endurance and strength. Start slow, and increase your time, distance and intensity gradually, even if you were previously well-trained.

23 To get fit, walk 20 to 30 minutes, 3 to 4 days a week at a fast pace, about 4.5 miles per hour.

24 Avoid the sore shins of a beginner. Balance and strengthen your calf and shin muscles by walking on your heels with your toes lifted. Stay upright and take short strides for 15 to 20 steps, then walk the same distance on your toes.

25 Turn a walk into a moving meditation. slow down your pace and notice your surroundings, count your footsteps or repeat a mantra. Lengthen your inhale and exhale, and concentrate on your walking rhythm.

26 Always wear reflective clothing when walking at dawn or dusk. More than 4,800 pedestrians were killed on U.S. roadways in 2002. Most accidents occur after 6 p.m. on Fridays and Saturdays.