do not show 'speed avg' column when there is no data
do not show 'speed avg' column when there is no data

- example: indoor training

mourningsun75/openmoves,bwaldvogel/openmoves,marguslt/openmoves,bwaldvogel/openmoves,mourningsun75/openmoves,marguslt/openmoves,bwaldvogel/openmoves,mourningsun75/openmoves,marguslt/openmoves