A brisk walk is about 3 miles an hour, which is faster than a stroll. To get any real health benefits you need to walk over 3 mph for 20 minutes or longer in one stretch. While walking slower or in short bursts has some benefit, you need to get your heart rate up (and burn more calories) for a real cardio benefit.
Men age 17-25 should complete 5 miles in a 83 minute period and Men 25-35 should complete 5 miles in 87 minutes. Women in the 17-21 age range, should complete 5 miles in 85 minutes with Women 25-35 achieving 88 minutes.
Over 35s Men over 35 should complete 5 miles in a 90 minute period and Women over 35 should complete 5 miles in 92 minutes.
Over 60s Men over 60, should complete 5 miles in 93 minutes with Women over 60 managing it in 95.
Safety It goes without saying, consult your doctor before starting miles, especially as you get older, if you have health concerns or have not had a recent check up.
3 miles should take about 50 minutes on average.
Calories Burned in 50 minutes
Weight 100lb:139
Weight 120lb:167
Weight 125lb:174
Weight 150lb:208
Weight 175lb:243
Weight 200lb:278
Weight 250lb:347
Weight 300lb:417
Calories Burned in 40 minutes
Weight 100lb:111
Weight 120lb:133
Weight 125lb:139
Weight 150lb:167
Weight 175lb:194
Weight 200lb:222
Weight 250lb:278
Weight 300lb:333
Calories Burned in 45 minutes
Weight 100lb:125
Weight 120lb:150
Weight 125lb:156
Weight 150lb:188
Weight 175lb:219
Weight 200lb:250
Weight 250lb:313
Weight 300lb:375
Calories Burned in 1 hour 15 mins
Weight 100lb:208
Weight 120lb:250
Weight 125lb:260
Weight 150lb:313
Weight 175lb:365
Weight 200lb:417
Weight 250lb:521
Weight 300lb:625
Calories Burned in 1 hour 15 mins
Weight 100lb:208
Weight 120lb:250
Weight 125lb:260
Weight 150lb:313
Weight 175lb:365
Weight 200lb:417
Weight 250lb:521
Weight 300lb:625
Calories Burned in 1 hour 30 mins
Weight 100lb:250
Weight 120lb:300
Weight 125lb:313
Weight 150lb:375
Weight 175lb:438
Weight 200lb:500
Weight 250lb:625
Weight 300lb:750