I like to run and my dog has a lot of energy so I take her running with me and occasionally tie her to my bike and we go for a ride. What should be the limits as far as distance or time with this 1yr, 3-4mo lab mix? How often do dogs need water? Will she need a coat or any paw protection during the winter? (it gets to about 20 degrees)
Sounds like your dog has a wonderful life and labs certainly have energy to burn!! Go for as long as both of you are comfortable, she will let you know when she starts to tire or is in need of a drink. Tell-tale signs are panting excessively (note though that any form of strenuous exercise will make her pant as this is dogs way of losing heat - it is only a problem if she seems to be fatigued at the same time), slowing of gait, insisting on stopping etc.
Take a drink bottle full of fresh cold water with you, I'm sure you'll appreciate some yourself, but you can pour some into your hand to let her drink from or even better exercise near a clean flowing river and stop and let her drink from time to time.
With regards to the cold, exercising should keep her warm. Take note of her pads and if they seem to get tender then you could try exercising during the middle of the days when it is warmest or on a different terrain, maybe the beach? Or soft dirt? During the colder months you may find you need to feed her a bit more as she will burn more energy keeping her body temperature up.
