Population:

16 children with cerebral palsy, GMFCS 1-3.16 children typically developed, matched for age.

All children aged 6-12 yrs who understand simple commands.

Tools:

1. Polar monitor to record heart rate, attached to chest, in use throughout testing
2. Dynamometer- for assessing muscle strength.
3. Weights

Method:

Each child will be tested once. Both tools will be demonstrated and tried out before actual testing.

With Polar watch attached:

1. 5 min sitting at rest,
2. knee muscle strength assessment with the dynamometer,
3. 15 minutes rest
4. Isometric and isotonic knee muscle contraction at 30% of childs' maximal strength as has assessed by the dynamometer. The child will asked to perform each for 3 minutes, with 5 minutes rest in-between All will be perform in both legs.

Inclusion Criteria:

• GMFCS I-II
• Unilateral CP

Exclusion Criteria:

• Heart problems

children with cerebral palsy