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Abdominal Crunches

Focus on technique as this exercise is often done incorrectly. Sit on the bench, knees bent with hands on thighs, or on temples for beginners. Lower your back until the middle touches the bench, flex forward, contracting the abdominal muscles with your spine folding at the bellybutton, stopping short of sitting upright, exhaling as you come up.
BEGINNERS do three sets of eight repetitions.
ADVANCED do three sets of 25 repetitions.
WORK IT for core strength and stability to avoid injury, focusing on deep abdominal muscles.


Great for runners, this exercise imitates running and strengthens leg muscles. Starting from the ground step up onto the bench with the left leg then raise the right knee to 90. Lower the right leg to lightly tap the ground and bring the knee up again, doing 10 repetitions. Switch to the left leg and repeat.
BEGINNERS do three sets of 10 repetitions each leg.
ADVANCED do five sets of 25 repetitions.
WORK IT to strengthen and tone legs, including quadriceps, glutes, calves and hamstrings.

205_s3_01.jpg1. Make the bench frame

On the bearers mark the trimmers 100mm from the ends and at the centre, drilling 4mm clearance holes, securing with 75mm screws. Position the decking with 10mm overhang, with short boards at the ends, securing from end to end.

Having drilled the pilot holes for the slats, consider painting them before assembly. Hang them up to dry, using the pilot holes as attachment points.

2. Finish posts and add pipe

Chamfer the top of the posts, sanding with 80-grit abrasive paper. On the foot posts mark 100mm from the top, wrapping cardboard around to mark a square line to drill a hole for the galvanised pipe, securing it with cuphead bolts.

3. Attach the foot posts

Drill 10mm holes, 50mm from the end of the bearers, and position the posts over the bench with a 175mm space between the bed and the pipe. Drill through the bearers and the posts, assembling with 175mm bolts, washers and lock nut.

4. Fit bench to head posts

Lift the bench until level, using a spirit level to check. Mark the base of the bearers on the inside of the posts, clamp and drill four holes 75mm apart through the posts. Slide adjustable bolts through to support the bench.


(measurements in mm)

Part                 Size                  No.
Posts (H4)  1200 x 100 4
Bearers (H3) 2300 x 90 x 45        2
Trimmers             360 x 90 x 45 3
Decking              470 x 90 x 20         21
450 x 90 x 20         3
Galvanised pipe 600 x 25 1

For each station use 125 x 10mm galvanised cuphead bolts to anchor the pipe to the posts, and 175 x 10mm galvanised cuphead bolts to secure the bearers to the posts of the sit-up bench.
Fit the bolts with 10mm washers, securing using galvanised lock nuts.
WEATHERPROOFING Avoid rust by using galvanised or treated pine fasteners for the decking, and give all the timber two coats of exterior paint to seal.

TIP We used Dulux Primer for New Wood, followed by Dulux in Plush Velvet 2.

All the products required for this project are available from Builders Warehouse.


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Bathroom use accounts for about 75% of the water used inside the home. Take shorter showers

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