The most common plank is the forearm plank which is held in a push-up-like position, with the body's weight borne on forearms, elbows, and toes. Many variations exist such as the side plank and the reverse plank. The plank is commonly practiced in Pilates and yoga, and by those training for boxing and other sports.
The "extended plank" adds substantial difficulty to the standard plank exercise. To perform the extended plank, a person begins in the push-up position and then extends the arms or hands as far forward as possible.
The plank strengthens the abdominals, back and shoulders. Muscles involved in the front plank include:
- Primary muscles: erector spinae, rectus abdominis (abs), and transverse abdominis.
- Secondary muscles (synergists/segmental stabilizers): trapezius (traps), rhomboids, rotator cuff, the anterior, medial, and posterior deltoid muscles (delts), pectorals (pecs), serratus anterior, gluteus maximus (glutes), quadriceps (quads), and gastrocnemius.
Muscles involved in the side plank include:
Guinness World Records lists the record for longest duration of a front plank, resting on elbows, as 9 hours, 30 minutes 1 second set by Daniel Scali. The former record of 8 hours 15 minutes and 15 seconds, was set by veteran Marine officer George Hood on February 20, 2020. Hood also completed a record attempt in June 2018, holding a plank for 10 hours, 10 minutes and 10 seconds as well as the most cumulative plank time in a 24-hour period of 18 hours, 10 minutes and 10 seconds.
The longest time in an elbow plank:
- by a woman is 4 hours, 19 minutes and 55 seconds by Dana Glowacka (Canada) in May 2019.
- by a woman with a 60-lb pack is 17 min and 26 sec by Eva Bulzomi (USA) in July 2013.
- with a 100-lb pack is 17 min 02 sec by Silehm Boussehaba (France) in December 2018.
- with a 200-lb pack is 4 min 2 sec by Silehm Boussehaba (France) in March 2018.
The longest single-arm plank while balancing on medicine balls is 47.54 seconds, by William Borger (Canada) in October 2016.
Medicine ball plank
- Knack Weight Training for Women: Step-by-Step Exercises for Weight Loss, Leah Garcia, p. 57. Quote:"Plank variations are abundant, and small changes increase the intensity of the exercise."
- Weight Training for Dummies, Liz Neporent, Suzanne Schlosberg, Shirley J. Archer, p. 263.
- Core Strength For Dummies, LaReine Chabut. Quote:"It's used in all yoga sun salutations and other poses. It is also a Pilates-based exercise used in many of Joseph Pilates exercises..."
- Pocket Guide to Fitness, Louiza Patsis, p. 176. Quote:"The "plank exercise" is used in Pilates classes."
- Kettlebells for Dummies, Sarah Lurie, p.260. Quote:"If you've done other exercises like yoga or Pilates before, you may be familiar with the plank position already."
- "Periodic Table of Bodyweight Exercises - Stack 52".
- "The Plank". Boot Camp & Military Fitness Institute. 2013-12-02. Retrieved 2019-08-07.
-  Longest plank record smashed with staggering new time Guinness World Record, September 4, 2021
- Guinness world record for planking set by 62-year-old former Marine George E. Hood The Washington Post, February 25, 2020
- Routine of George Hood who set world record for planking CNBC, March 2, 2020
- At 62, Marine veteran sets the Guinness record with 8-plus hour plank marinecorpstimes.com February 24, 2020
- Stephenson, Kristen (2020-02-20) Former US Marine just broke an 8 hour plank record – and he’s 62 years old Guinness World Records Retrieved 2020-02-22.
- 62-Year-Old George Hood Broke The World Record For Holding A Plank Forbes, February 24, 2020
- A fitness instructor from Aurora has set 2 world records Chicago Tribune
- Danger, Jessica (2018-06-29). "Retired Marine Sets 10+ Hour Plank World Record". Morning Chalk Up. Retrieved 2019-10-05.
- "Longest time in an abdominal plank position (female)". Guinness World Records.
- "Longest time in an abdominal plank position with a 60-lb pack (female)". Guinness World Records.
- "Longest time in an abdominal plank position with a 100 lb pack". Guinness World Records.
- "Longest time in an abdominal plank position with a 200-lb pack". Guinness World Records.
- "Longest single-arm plank while balancing on medicine balls". Guinness World Records.
- Media related to Planks at Wikimedia Commons