For background and context for the information below, see the SOP factor section home page.
Physical activity - METs
More than 50 RMA SOP conditions have factors that concern a level of physical activity, in METs.
METs are a measure of energy expenditure per minute. One MET is the energy used when at rest for one minute. If an activity has a value of 4 METs it means that it requires four times the energy than is required by sitting still.
Energy expenditure differs from person to person based on several factors, including age and fitness level. A young athlete who exercises daily won’t need to expend the same amount of energy during a brisk walk (e.g.) as an older, sedentary person.
Average METs levels have been estimated for a very wide range of activities.
For example, walking at 4 km/hr on flat ground is given an average METs level of 3, whereas walking fast, on flat ground, at 6.5 km/hr, attracts a METs level of 5.
For any given activity the METs level very much depends on the intensity of effort involved. An activity performed vigorously may have twice the METs level of the same activity performed at light intensity.
The maximum METs level a person can achieve depends on their fitness level and physiological capacity. Sustained fast running at > 20 km/hr involves an expenditure of 20 METs or more.
SOPs have METs factors in two main types:
1. Inability to undertake physical activity
2. Undertaking physical activity at a minimum level
1. Inability to undertake physical activity
This factor (in approximately 27 SOPs) requires that a person is unable to perform any physical activity above the level of 3* METs. That inability has to be present over an extended period of time.# This lack of exercise is a risk factor for a variety of benign and malignant chronic diseases, typically occurring in older persons.
* The diabetes mellitus SOP is the one exception, stipulating “at least four METs” rather
than “greater than three METs”.
# Mostly for 5 or 10 years, but for one year for some conditions.
Being unable to undertake any activities above 3 METs requires a severe level of disability, such as would be found with severe cardiorespiratory disease or significant neurological impairment.
This SOP factor is very unlikely to apply to someone who is fit for service in the ADF. Being able to pass a Basic Fitness Assessment would preclude meeting this factor.
A person who is limited in undertaking some activities > 3 METs due to a localised disease or injury, e.g. a lower limb disorder, may still be able to undertake other activities > 3 METs that involve, e.g., only the use of the upper limbs, or where body weight is supported by water.
Table 1. Activities that require (on average) > 3 METs include:
Activity | Average METs rating |
Walking at or above 4.3 Km /hr (2.6 mph) on firm level surface | > 3 |
Walking down stairs | 3.5 |
Walking slowly carrying objects 1 to 10 kg | > 3 |
Swimming leisurely | > 5 |
Water exercises / aerobics | 5.3 |
Upper body exercises e.g. arm ergo – moderate effort | > 4.3 |
Resistance (weight) training / exercises | > 3.5 |
Stationary cycling – light effort | > 3.5 |
Riding a motorcycle | 3.5 |
Playing table tennis | 4.0 |
Playing lawn bowls | 3.3 |
Playing golf using power cart | 3.5 |
Loading / unloading a car | 3.5 |
Standing and packing/unpacking boxes | 3.5 |
Making a bed / changing linen | 3.3 |
General kitchen activity – cooking, washing dishes, cleaning up | 3.3 |
Housework – light effort: vacuuming, taking out garbage | 3.3 |
Gardening – light effort, weeding, picking flowers/vegetables/fruit | > 3.3 |
Yard work – using a leaf blower, raking leaves, mowing lawn (walking) | > 3.5 |
Automobile repair/maintenance | > 3.3 |
Washing a car | 3.5 |
Painting a room | 3.3 |
> 3 |
2. Undertaking physical activity at a minimum level
There are several sub-types of SOP factors:
a. Factors for moderate short term activity within a short time before the onset of an acute illness or event.
(i) Factors for activity involving a particular joint/specific movement, over a period of weeks,
for overuse lower limb conditions; and
(ii) Corresponding factors for a doubling (or more) of a previous amount of activity for at
least 2 hours per day for the seven days before onset of an overuse lower limb condition.
(iii) A varicocoele SOP factor for unspecified sustained activities for 6 hrs/wk for 4 weeks.
c. Long term higher intensity activity factors, for several arrhythmias
The METs levels specified in SOP factors of this type are either ≥ 5 METs, ≥ 6 METs, or > 6 METs (except for exertional heat illness, which requires only ≥ 3 METs).
5 to 6 METs is exercise of moderate intensity, comparable to fast walking, that will result in a noticeable increase in breathing and heart rate, but will be well below the maximum effort possible for a fit healthy person.
Factors for moderate short term activity
SOP factors of this type all stipulate a minimum level of either 5 or 6 METs, except for exertional heat illness which requires at least 3 METs.
The METS level for any given activity depends on the intensity of effort and also on how sustained the effort is.
Examples of activities (including ADF activities) that typically involve a minimum of 5 METs:
- walking at 6.5 km/hr (4.0 mph), on a level, firm surface (very brisk pace)
- walking up hills at 5 km/hr
- walking carrying a pack or load ≥ 15 kg
- Cycling > 15 km/hr
- Gym workout – moderate to vigorous intensity
- Digging / Shovelling – moderate effort e.g. digging weapons pit by hand, filling sandbags
- Using heavy power tools (e.g. field engineer felling trees using chain saw)
Examples of activities (including ADF activities) that typically involve a minimum of 6 METs:
- walking at ≥ 7 km/hr, on a level, firm surface
- running/jogging
- walking carrying a pack, load or webbing ≥ 25 kg
- walking/climbing up hills carrying a load ≥ 5 kg
- ascending stairs, ladders, cargo nets
- Carrying moderate loads up stairs (boxes/ stores)
- Cycling ≥ 18 km/hr
- circuit training – moderate to vigorous intensity
- Weight lifting – vigorous effort
- Physical training, carrying logs/ heavy loads
- Sport (including ADF sport) involving constant movement with frequent bouts of running (e.g. football - various codes, hockey, basketball, squash)
- Fire fighting activities e.g. hauling hoses, climbing ladders with full gear
- building roads - Construction engineers, manual effort
- Fire and movement actions
- Leopard crawl
Sustained activity factors
Factors in the overuse lower limb condition SOPs require activity:
- Of at least 5 METs*;
- For at least four hours# per week;
- For at least four weeksⱡ; and
- Involving movement or loading of a particular joint or part of the affected leg.
* 6 METS for patellar tendinopathy and popliteal entrapment syndrome
# 20 hrs/wk for popliteal entrapment syndrom
ⱡ 3 months for plantar fasciitis & 6 months for popliteal entrapment syndrome
Examples of activities that meet these requirements can be found by using the following two tables in conjunction (Tables 2 & 3). Identify the letter category for the SOP condition using the first table, then identify relevant activities for that SOP condition using the second table.
Table 2.
SOP Condition | Activity specified in SOP | Category |
Achilles tendinopathy or bursitis | repeated activity of the ankle joint | E |
chondromalacia patella | forceful loading of the affected patellofemoral joint | D |
femoroacetabular impingement syndrome | repeated activity of the hip | A |
iliotibial band syndrome | repeated flexion and extension of the affected knee | B |
patellar tendinopathy | jumping or repeated flexion and extension of the affected knee > 6 METs | C |
plantar fasciitis | repetitive weight bearing on the affected foot | F |
popliteal entrapment syndrome | repeated active plantar flexion of the foot ≥ 6 METs | G |
posterior tibialis tendinopathy | repeated activity of the ankle joint | E |
shin splints | Repeated activity of the lower leg | H |
trochanteric bursitis or gluteal tendinopathy | repeated activity of the hip | A |
Table 3.
Activity | A | B | C | D | E | F | G | H |
walking, 6.5 km/hr (4.0 mph), level, firm surface, very brisk | Yes | Yes | No | No | Yes | Yes | No | Yes |
walking at 7 km/hr, on a level, firm surface | Yes | Yes | Yes | No | Yes | Yes | Yes | No |
Running or jogging | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Marching with pack/load 15-25 kg | Yes | Yes | No | No | Yes | Yes | No | Yes |
Marching with pack/load > 25 kg | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Ascending ladders/stairs/cargo net | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes |
Playing team sport involving repeated running | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Cycling > 18 km/hr | Yes | Yes | Yes | No | Yes | No | Yes | Yes |
Yes | Yes | Yes | No | No | No | No | Yes |
Long term (5 years) higher intensity activity factors
Factors in this category require activity:
- Greater than 6 METs;
- For at least 20 hours per week on average;
- For at least 5 years.
This level of activity will most likely be seen in serious/professional athletes who train for and undertake endurance events. It will also likely be seen in SAS / Special Forces personnel / Navy clearance divers undertaking training for and performing active duties in those roles.