Low energy times ahead? (Part two)

Obviously this drop in Watts as we age and its consequences comes as no surprise as VO₂ max declines due to reduced cardiac output and oxygen utilization. This also goes along a decrease of muscle mass and mitochondrial density decrease (that volume of mitochondria within a cell, represents the cell's capacity for energy production).

A higher mitochondrial density means more mitochondria are present, leading to a greater ability to produce ATP or adenosine triphosphate, an energy-carrying molecule found in all living cells, and that fuels our aerobic activities. To make matters worse, neuromuscular efficiency wanes, recovery time increases, thus limiting the time and frequency we devote to training. 

Now, to counteract a bit this depressing list, it’s true that older athletes often become more efficient as their pacing improves and they become smarter in the way they train and produce efforts. So while raw wattage may decline, performance per watt—especially in endurance events—can remain surprisingly high. 

While most athletic performance data tapers off around age 70, there’s now research and anecdotal evidence that extends into the 80s and 90s, especially from masters athletes and a long-term follow up of certain individuals. Again that data comes from cycling FTP (Functional Threshold Power) and VO₂ max studies, which correlate strongly with watt output. 

Check again the chart we showed yesterday as it applies to over 70 people. These are averages, and trained individuals can exceed them. 

The decline is roughly 20–25% per decade after 70 and accelerating due to a variety of factors, like sarcopenia (muscle loss), reduced mitochondrial efficiency, slower neuromuscular response and longer recovery times. 

This is where a philosophical lens should sharpen the picture. Physiologically, the decline is real, but not linear, and not purely physical. 

We need to look at a more layered view; our power output may drop below 100W in late 80s/90s and VO₂ max can fall to 15–20 ml/kg/min (from our younger 40s) and our daily energy feels like shrinking, with less reserve and slower recovery. Mentally, there’s also our cognitive and emotional energies, where mental clarity often remains surprisingly intact, especially in reflective individuals. 

At the same time our emotional resilience may deepen, even as physical capacity wanes and this is when a sense of purpose and the riches of our connection become key drivers of perceived vitality. In fine, we should see our last year as a path to a crescendo, when from 70 to 80 we’re still capable, but adapting. In the 80-90s we need to switch to more selective energy use, less output but often more wisdom and over our 90s – if we make it that far - the wattage may be low, but the signal can still be strong as long as the mind and heart remain engaged. 

There’s always a glimmer of hope, so tomorrow we’ll see how we can aim for it!