If you're like many fitness enthusiasts, you will be doing some cardio as well as resistance training, whatever form that may take. Your cardio sessions might even be combined with a weights session, as occurs in some forms of circuit training, or even in a single gym workout with treadmill and weights.
If your cardio preference is to jog or run, as it is for many, you might like to consider how best to organize a training program that includes both training types. In fact, you might even be doing some high-intensity running intervals that border on the aerobic / anaerobic threshold. This type of high-intensity training is a good way to build fitness quickly -- if you can handle the intensity -- but fatigue can play havoc with your weight training if you don't approach it intelligently.
Running, Lifting and Fuels
The distinction between 'running' and 'jogging' can mean the intensity at which you perform. This has relevance to your resistance work because of the fuels that each use for energy. Running might reasonably be defined as activity in the range 70-85% of maximum heart rate (MHR) for most people. Beyond 85% is entering high-intensity interval territory, and even though runners will break through into this intensity zone when racing at some point, most runners do most of their training between 70-85% MHR. Some with heart disease or very poor fitness might even reach this threshold while walking. Jogging on the other hand, for the average jogger, we'll define as in the range 50-70% of maximum heart rate.
Now here's the point: At the higher intensity you will be using more carbohydrate (as glucose), and at the lower intensity, you will use more fat. For the most part, your weight training or resistance training session will use glucose as fuel because the short, sharp pushes and pulls in the gym mostly are in the higher intensity zone. You don't want to exhaust your glucose muscle supplies before your weights session or your running session.
Timing Your Sessions
If your training program includes running and weight training you need to separate your sessions for best effect and progress. Here's a possible program:
- Day 1 - AM Resistance; PM Running 60 minutes (6 hours separation, refuel between)
- Day 2 - AM - Rest; PM Jogging 40 minutes, Resistance (single session, refuel)
- Day 3 - AM - Running 45 minutes
- Day 4 - Rest
- Day 5 - AM - Resistance; PM Running 60 minutes (6 hours separation, refuel between)
- Day 6 - AM - High-intensity intervals 30 minutes
- Day 7 - Rest
The principle here is that if you train with weights and running on the same day, then you should try to rest as much as possible between sessions and refuel in the interval. When doing a slow, jogging session, you can even squeeze both workouts in to a single session at the gym with the jogging done on the treadmill. Topping up with half a bottle of sports drink between the treadmill and the weights session will ensure you have plenty of muscle glycogen to work hard in the weights workout.
As explained in this article: The Best Sequence of Cardio and Weights, providing you don't hammer yourself hard, moderate aerobic work before a weights session will not have a measurable effect on your weights workout performance. However, running or jogging immediately after a weights session is not ideal because at this time you should refuel and maximize muscle protein synthesis and rebuilding.
In summary, for all-round fitness, you can easily mix running, weights and even interval training providing you pay attention to timing, rest and refueling. If you're a marathoner or Olympic lifter, then you may have to pay more attention to your target sport than is suggested here.