For decades, Singapore Army soldiers have done five basic exercises - jumping jacks, high jumper, crunches, push-ups and running - as part of their morning routine to warm up their bodies.
But no longer, as the 5BX ritual has been replaced with stretching and strengthening drills meant to improve mobility and flexibility, as well as reduce common injuries faced by soldiers in the knees, ankles and back.
The change in exercise regimen is part of a recent review by the army to help soldiers train, sleep and eat better.
In place of 5BX are Prehabilitation Exercises (PX), approved for armywide use since April after a successful trial in the Officer Cadet School (OCS) in 2018 and 2019.
Now, mountain climbers, forward lunges, alternate arm and leg raises, among other exercises, will form the new standard.
About 90 per cent of army trainers and units are currently on board, with the rest to join by the year end, said Lieutenant-Colonel Chong Yi Tat in a virtual interview with reporters yesterday.
LTC Chong, 38, is head of training and development at the Centre of Excellence for Soldier Performance (CESP).
Founded in 2017, CESP is part of the army's push to use sports science, psychology and nutrition to improve soldier performance.
Army units have a choice of two exercise programmes, one with 14 exercises and the other with 15.
Each exercise is to be done for 30 seconds at a slow tempo.
Ms Grace Heng, 43, head physiotherapist at CESP, said: "Unlike high-tempo and high-intensity exercises that (the) army does to build physical fitness, PX focuses on form and controlled movement."
PX also allows for more flexibility than the 5BX regime, she added.
The workouts can last for either 15 or 30 minutes at any time of the day, unlike 5BX, which is a single routine done right after waking up in the morning.
Although PX is less strenuous than 5BX, fitness is not compromised, stressed LTC Chong.
Fitness training remains embedded in the larger training system, with PX complementing it.
Fitness test results were comparable between the control group and the test group at OCS.
But the injury rate was 6.3 per cent in the control group which still did the 5BX, and 2.6 per cent in the 1,100-strong test group.
"The lower rate of musculoskeletal injuries translated to better performance during military training, such as mission exercises and live firing," said LTC Chong.
PX is one of three prongs under the army's Strong Body Regime, an initiative aimed at reducing the risk of injuries and enhancing soldier performance.
The other two prongs, which were also trialled at OCS, involve improved nutrition with snacks between meals and two hours more of rest time to promote recovery.
Ms Rachel Leah Yeow, a nutrition officer at CESP, said carbohydrate-rich snacks are given before soldiers engage in cardiovascular exercises while protein-rich snacks are provided after strength training.
"The intent (of) nutritional supplementation is to enhance soldier performance and recovery," said Ms Yeow, 29.
These snacks are recommended for soldiers undertaking at least two moderate or strenuous activities a day, in addition to existing guidelines that provide snacks for servicemen training at night.
Two hours more of rest time on any day from Tuesday to Thursday is also recommended for units with three or more strenuous activities, such as field training, in a week - although not for reservists.
First Warrant Officer Arivalagan Kottamuthu, 49, a platoon commander at the Basic Military Training Centre, called PX a good initiative to prevent injury.
"(5BX) makes (servicemen) tired, whereas for PX, they feel refreshed and awake for upcoming activities," he said.
Lance Corporal Abdul Hadziq Abdull Hamid, 19, an infantry trooper at the 5th Battalion Singapore Infantry Regiment, said PX has made strenuous route marches easier.
"I find it easier now because PX actually starts up the body and stretches out the muscles to prevent muscle injury."