How hard is too hard?

Question: How can you tell if you are running too fast or you are starting to struggle and should slow your pace?

In order to maintain the effectiveness of a Tempo or an Interval workout it is important that you maintain a certain pace or level of effort during the workout. So if for any reason (Tired, sick, overworked) you can't maintain your pace, you should axe your run and make it up another time. But how do you know?

Signs before you head out.
The obvious ones are that you haven't slept well or that you have had a particularly busy day. If you are someone who tracks your vitals in the morning, RHR, Blood Pressure, Weight and Hours slept, then you will know right away if this is going to be a good or a bad day. Most people have a pretty good idea just rolling out of bed in the morning.

Signs during a run that you should ease off because your pace is more than your body can handle:

• Difficulty catching breath
• Tingling / Numbness in fingers or toes
• Blurred eyesight (the old one eye)
• Headache
• Tightness/stiffness in shoulders
• Inability to do simple math in head (converting miles to km)
• Heavy Feet, you start to stumble and catch your feet on sidewalk chalk.
• Check your posture, how old do you look? Stand up, Run Tall!
• If you wear a HRM, then you can accurately track how you are doing.

Whether it's a 3 km interval or a 12 km Tempo, it's still important to work within your training zone and get the workout that you are there for. Quality always wins over Quantity.