Method and an apparatus for determining injury risk of a person based on physiological data

1. A method for determining injury risk of a user from plurality of exercises using a device with a heart rate sensor, a processor, memory including a resident memory, an output display device, the injury risk being determined using values depicting Short Term Training Load and Long Term Training Load, the method comprising:

determining in each physical exercise a timestamp and a value of Short Term Training load and Long Term Training Load utilizing the heart rate sensor,

storing the timestamp and the values of Short Term and Long Term Training load of each exercise in the resident memory obtaining a register having plurality of Short Term and Long Term values from executed exercises,

at least one per week, automatically performing a HRV-based Recovery Test utilizing the heart rate sensor and obtaining a Recovery value with a time stamp from each Recovery Test and storing said Recovery values with the time stamp in the register of the resident memory,

calculating indices depicting Short Term Training Load, ratio of Short Term Training Load to Long Term Training Load, and Recovery based on the values stored in the register,

calculating weighting factors for each said index, each weighting factor depicting relevance of corresponding index to user's probability of injury,

correcting each index with corresponding weighting factor to obtain weighted indices,

calculating a numerical value of the Injury Risk using the weighted indices, and

displaying the value of Injury Risk to user using the output display device.

2. The method according to claim 1 , wherein said indices are calculated using scaling functions which are namely first scaling function for calculating a first index depicting Short Term Training Load, second scaling function for calculating a second index depicting ratio of Short Term Training Load to Long Term Training Load and third scaling function for calculating a third index depicting Recovery.

3. The method according to claim 2 , wherein if highest value of injury risk depicts lowest possible probability of injury, the first scaling function is such that value of the first index increases to maximum as the value of Short Term Training Load increases up to a predetermined value and the value of the first index decreases as the value of Short Term Training Load increases higher than the predetermined value,

the second scaling function is such that value of second index reduces when value of ratio of Short Term Training Load (STTL) to Long Term Training Load (LTTL) differs from 1 and the third scaling function is such that value of the third index increases when the Recovery Test result increases until a threshold value of Recovery test has been reached.

4. The method according to claim 2 , wherein said third index is calculated by

a. obtaining at least two, preferably three latest Recovery values,

b. scaling the Recovery values using third scaling function,

c. calculating a second average of the scaled Recovery values, the second average being the third index.

5. The method according to claim 1 , the Recovery Test is a Quick Recovery Test having a duration of 1-10 minutes.

6. The method according to claim 1 , the Recovery Test is a Quick Recovery Test having a duration of 2-4 minutes.

7. The method according to claim 1 , wherein the values of the indices are scaled in a predetermined range in a scale 0-100.

8. The method according to claim 1 , wherein said weighting factors are first weighting factor, second weighting factor and third weighting factor, wherein the first weighting factor is calculated using a first weighting function depicting reliability of the first index,

the second weighting factor is calculated using a second weighting function depicting reliability of the second index,

the third weighting factor is calculated using a third weighting function depicting reliability of the third index.

9. The method according to claim 8 , wherein the third weighting function is an average of values of a fourth weighting function, which is a function of timing of the recovery test, and a fifth weighting function which is a function of average recovery values.

10. The method according to claim 9 , wherein the third weighting factor is calculated by calculating

a. a sub-factor for each Recovery value using the fourth weighting function and the fifth weighting function,

b. an average of the sub-factors, the average being the third weighting factor.

11. The method according to claim 8 , wherein the calculation of Injury risk comprises: multiplying the indices each with a corresponding weighting function, in which

a. the first weighting function is constant,

b. the second weighting function increases the value of the second weighting factor as number of exercises per week increases,

c. the third weighting function gives a peak value for the third weighting factor at lowest recovery value.

12. The method according to claim 1 , wherein the calculation of Injury risk comprises: scaling the values of indices stored in the register to form scaled indices wherein

i. scaled value of the first index has a peak value before Short Term Training Load is 100% from user's personal maximum value,

ii. scaled value of the second index has a peak value when ratio is invariable,

iii. scaled value of the third index increases with improved recovery value until a peak value is reached,

storing scaled indices in the register of the resident memory.