Cardio after 40 should support heart health, work capacity and longevity without undermining recovery from resistance training.
Build an aerobic base
Moderate-intensity aerobic work that you can sustain while still speaking in short sentences is a useful foundation. Walking uphill, cycling, rowing and easy jogging are all viable options depending on joint tolerance and fitness.
Add some higher-intensity work
Intervals can improve cardiovascular fitness efficiently, but they are also more fatiguing. One or two focused interval sessions per week may be enough for many people when combined with regular lower-intensity work.
VO2 max matters
VO2 max is a measure of aerobic capacity and is strongly associated with overall fitness. Improving it usually requires training that challenges both the central cardiovascular system and working muscles.
Do not let cardio destroy leg training
If strength and muscle are major goals, manage timing and total fatigue. Hard running intervals immediately before heavy lower-body training may reduce performance. Separating demanding sessions can help.
Choose the mode you can repeat
The best cardio method is one you can perform consistently without aggravating injuries. Brisk incline walking may be more sustainable than running for one person, while cycling or rowing may suit another.
PRIME 40 shows how cardio and resistance training can fit together in a complete plan for fitness after 40.