You need two different prams (or possibly three).
Since you're avid runners, you should get a separate pram for that purpose. They are usually three-wheeled. The reason is that everyday prams aren't meant for high speeds. Look for ones that have:
- a long wheel base with fixed wheels (runs more straight)
- big, bicycle-style wheels (comfort)
- brake lever on the hand bar (safety)
These things are irrelevant at walking speeds but essential at running speeds.
For everyday trips to the grocery store etc. a regular pram would be much more convenient, not least because it's smaller/shorter and pivoting wheels give much better maneuverability (which is exactly what you want to avoid when running).
To really cover all situations, you would in fact need three strollers, the third being a small "umbrella stroller." They aren't appropriate for infants, but once the child is old enough to sit up on their own, these become good for situations like flights and trains, where size and weight matter more than short-term comfort. This is where you can save money: because these won't be used for long at a time, you don't need a brand-new, super-sturdy one with lots of features. Just pick up a used one for a few dollars. Make sure to test how small it is when folded closed.