new here, been running on treadmill for about seven months now.. walk 5 min run 40 min about5.6-6.6 mph then walk cool down another 5 min..usually 5 days per week..for the last month my legs have reallly hurt, thighs mainly i live on motrin. no problem until the last month or so..any suggestions or recommendations..wondering about electrolytes..i eat a very low carb diet so avoid sugary drinks..thanks