The best replacement for biking is running.

The best alternatives to biking are rated as following:
★★★★★  running
★★★★  walking
★★★★  jogging
★★  driving
★★  cycling
★  running calories
★  walking calories
★  road biking
★  skateboarding
★  running calories burned
  running cardio
  running miles
  running for cardio
  walking calories burned
  walking better
  skating
  mountain biking
  walking better exercise
  kayaking
  rowing
  swimming
  running burn more calories
  rollerblading
  walking burn more calories
  hiking
  jogging calories burned
  running workout

Your alternative for biking is not listed? Suggest!
Speaking about biking, one probably shouldn't forget about fitbit flex.

Other search terms related to biking and their ratings are:
★★★★★ fitbit flex
You have in mind a companion for biking and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of biking in all years. Click on graph for more.
biking
running
walking