1. Stand tall with feet together, step forward with your right leg and drop down into a lunge so that both knees are at 90 degrees and your body from hip to head is tall (no forward slouching).

2. Bring your left leg through (standing tall as you walk through) and continue to walk forward, drop down into a second lunge, and so on and so on, travelling across the office or the park as you go.

3. Stay tall in your upper body, and work through the walking lunges without wavering in balance or posture. Your legs will feel the effort after 10 to 15 lunges. Keep going until you fatigue. If you have knee problems, try not to dip down so far.

1. Lie on your back with hips elevated. Ensure knees are at approximately a 90-degree angle. Dig your heels into the floor and feel your hamstrings contract.

2. As you hold, try elevating your hips a few inches and lower back to the start, or try lifting one leg off the floor at a time.

If you're new to pushups do them with your hands on the top of the backrest on any park bench (the top of your desk will do too).

1. Place your hands about shoulder width apart with your chest lined up with the edge of the surface.

2. Lower your chest to meet your hands (keep your back long and your abs engaged), then push back up. Try 6-10 or more (until the last few are a challenge).

Challenge 2: Put your feet onto the park bench and your hands on the ground. It's harder this way because the leverage shifts from your stronger legs to your weaker upper body. Do as many as you can this way and then shift back to an easier level.

1. Stand tall with feet shoulder distance apart. Hold any heavy object (hole puncher or ream of paper) in each hand. Bend over from the waist, keeping your back straight, your abs engaged, and your knees slightly bent.

2. 'Fly' your arms up and out, squeezing into mid back as you finish. Repeat 12-15 times or until fatigued. Keep hands below shoulder level. The goal is to feel a 'squeeze' behind your shoulders and into the middle of your shoulder blades. Lower slowly to starting position and repeat.

1. Hold something relatively heavy in each hand (such as 4-L milk jugs full of water or your purse with a big book in it).

2. Hold the weight palm up in front of your body (elbows at 90 degrees). Curl toward your shoulders and back down to full extension.

1. Sit on chair with your buttocks just at the edge of the seat. Make sure your feet are positioned below knees to start (90-degree angle).

2. Place hands at sides, fingers overhanging the seat of the chair, and lift body weight onto your hands. Slip your behind off the chair and lower your body until your buttocks dip chair level (maybe a foot or so) then push back up.