There are several measures of strength; one is how much weight you can bench press. Meanwhile, chin-ups and push-ups attest to impressive upper-body strength, and a heavy deadlift is proof you've got strong legs, back and glutes.
To test both physical strength and mental toughness, nothing beats a good plank, reckons personal trainer Matt Chapman.
Chapman, also the founder of active compression wear company PocJox, wants to see what we're made of and has issued a 'Plank Challenge', to see how long participants can hold a plank for. He has set a benchmark himself, holding a plank for four minutes and 17 seconds.
To prove your planking prowess, you'll need to set up a camera, hit record and drop into position with your body in full view. Send the video along with your time to the PocJox Facebook page.
The winner each month will receive a prize, and the contestant at the top of the leaderboard at the end of the year will score a personal training pack with Chapman valued at $500. The pack will include a 30-minute consultation; a one-hour training session; one-month online training; nutritional advice and a PocJox pack.
Stability and balance
51698009's fitness columnist Michael Jarosky says planks are a great exercise not only for the core, but also challenging the biceps, neck, shoulders, chest, lower back, glutes, quads, and calves.
"Planks mainly test the inner core muscles which promote stability and balance, something every individual needs; male and female, old and young," Jarosky says.
Whether a plank is the best core strengthening exercise is open to debate, Jarosky believes, because it is not a dynamic movement. However, he remains a big fan.
"Planks are a challenging, isometric exercise that every man and woman should be able to do, and therefore it can be timed in a me-versus-you scenario, like a 100m race for the abs," he says.
He urges caution for those looking to set records. "In order to win, a contestant might hold a plank at the expense of spine health," he says. "When one starts to shake and the core is starting to weaken, the lower back can sag, and this can be very dangerous for the spine. Don't be a one-trick pony; use side planks for obliques and reverse planks for posterior health to train the entire core."
How to perform a standard plank
1. Plant the hands directly under the shoulders like you're about to do a push-up.
2. Ground the toes into the floor and squeeze the glutes to stabilise the body. Your legs should be working in the move, too.
3. Neutralise the neck and spine by looking at a spot on the floor about a foot in front. Your head should be in line with your back.
4. Once in position, hold your plank for as long as possible without compromising form.
How to perform a plank on elbows
1. Plant the elbows directly beneath your shoulders. The weight should be distributed beneath your upper arms, under the elbows. The forearms should be pointed in whichever direction is comfortable.
2. Shoulders must be packed down on the ribcage to connect the structure of the arms to the structure of the core muscles.
3. Activate the core musculature, while also contracting the glute muscles.
4 The best positioning for your feet is hip-width apart. For those with tighter hips or limited range of motion, it's OK to place your feet a little wider.
5. Once in position, hold your plank for as long as possible without compromising form.
Got any tips to a top plank? Let us know in the Comments section.