Recovery, Part 2: A Framework for Your Recovery Score
In my prior post on recovery, I shared a long list of metrics, all of which have some degree of scientific support and therefore might have some utility in reflecting recovery status. However, more data is not necessarily better; in fact, more data often muddies the water. The quality of the data—whether or not it is interpretable and actionable—is key. “Garbage in equals garbage out” as the saying goes. So it is useful to spend some time selecting the best inputs (based on the best available research to date) for what we can deem a “recovery score.”
We need to select the most accurate, precise, and practical metrics and to create simple ways to track them at appropriate intervals. To start, think of a “recovery score” on the continuum from fully recharged to overtrained. As we discussed, functional overreaching is a necessary stress to trigger the adaptations that make us stronger, fitter, and more resilient. So what we really want is a way to gauge when we are on the cusp of tipping into overtraining and burn out. We need a fuel light on our biological dashboard to alert us when our tank is getting close to empty. We need a reliable way to know when to take our foot off the gas and for how long until we can get back on the road. Ideally, we learn to adjust our speed in real time—with a smart training program, proper nutrition, restorative sleep, and ample hydration—such that we avoid the repair shop altogether.
If the purpose is to be proactive about recovery and guard against overtraining, there are certain metrics we should monitor regularly to make sure we are not veering into overtraining territory. While no one marker magically specifies recovery, some are better than others. A holistic combination of performance, physiological, biochemical, and psychological variables would seem to be the ideal strategy.
There are several criteria that a reliable marker for recovery must fulfil: the marker should be sensitive to the training load and ideally, be unaffected by other factors (e.g. diet). Changes in the marker should occur prior to the onset of an overtrained state so we can adjust accordingly. Changes in response to acute stress, i.e. an intense training session, should be distinguishable from chronic changes. And finally, the marker should be relatively easy to measure and not too expensive. Here is my best shot at a reliable and reasonable approach broken down by how often and what type of metrics to track.
Daily Physiological and Psychological Metrics
Your physiology and psychology change day to day in response to your level of recovery. The key is to assess these variables on a regular (ideally daily) basis in order to distinguish spurious abnormality from worrisome trend.
Heart rate: keep a pulse (pun intended) on your heart rate, first thing each morning before you get out of bed. Over time you will find an average or baseline. If your resting heart rate is unusually high or low for multiple days in a row, this is might signal inadequate recovery. Preferably, however, you invest in the improving technology to track your heart rate variability (HRV). HRV is a simple, quantified reflection of the balance between your sympathetic and parasympathetic inputs from your autonomic nervous system
Thirst: if your body is existing into a catabolic state (meaning you are consuming your own muscle protein), this can cause serious dehydration. So if you are excessively thirsty, take note.
Duration of muscle soreness: it is normal to have sore muscles for a day or two following a training session. But if you hit the 72-hour mark and are still experiencing serious soreness that limits your mobility, this is a sign that your muscles are not recovering properly from your training stimulus and it is time to dial it back.
Sleep quality: your body grows while you are resting, not while you are training. And so sleep is the magical elixir for recovery, in particular the first few hours of sleep when growth hormone surges. If you cannot sleep soundly, even though you are physically exhausting yourself, this may mean that your nervous system is fried and your hormones are out of whack.
Mood: physical exertion is generally a mood booster. In fact, regular exercise is a potent antidote for depression. However, if your recovery is sub-par, excess training can have the opposite effect and cause you to feel depressed, irritable, and aggressive.
Decreased focus and motivation: sure, we all have “off” days. But if you are usually energized and ready to attack the day and then find yourself in a slump, this may be the result of excess stress without balanced recuperation.
Illness/injury: if you are coming down with colds or suffering from aches and pains on a regular basis, this is your body’s way of telling you that your immune system is struggling. If you are not balancing intense training with proper recovery, your body will be in a continual catabolic state which lowers immunity and increases the risk of illness.
Weekly Performance Metrics
Choose a series of performance-based tests that align with your fitness goals. For example, consider a timed 1-mile run for cardiovascular fitness, a volume of squats and bench presses for strength, a 50-yard dash for speed and power, or certain poses for mobility. Track your progress on these physical tests to set a fitness benchmark. Each week or so, you perform these routines as part of your training plan. If your progress stalls, or perhaps backslides, then you know it’s time to build more recovery into your plan so your body can fully assimilate your training stimulus.
Biochemical Metrics
Biomarker testing and analysis poses many challenges. Most biomarkers are crude and nonspecific for reflecting a broad physiological function such as “recovery”. Markers of inflammation and muscle breakdown, hormone levels, and immune mediators can vary widely over the course of a day and often have multiple effects in the body.
Relying on a single marker to sensitively and precisely detect overtraining is overly simplistic. Instead, a battery of multiple validated biomarkers— markers of hydration state, nutrition/metabolic health, oxygen transport, muscle status, inflammation, injury risk—increases sensitivity. As an example, Lee and colleagues propose a variety of well validated markers that could all be part of a comprehensive panel:
The key with biomarker analysis is to compare levels to an established baseline. Although these tests have “normal ranges,” the levels of markers vary from person to person based on BMI, athletic status, gender, ethnicity, genetics, etc. Proper interpretation necessitates a relative comparison. Checking these values on a bi-annual basis provides enough data over time to establish an individual’s unique baseline, identify trends, and take corrective actions when necessary.
Finally (and perhaps most importantly), you must interpret the output of your recovery tests in the context of your unique life variables and trends. Factors such as age, gender, lifestyle, and hormones all influence these metrics. And “stress” comes in many flavors. Suppose, for instance, that you are cramming for a test or pressing to meet a work deadline. The ensuing sleep deprivation, over-caffeination, and high-sugar diet all contribute to a poor recovery state. Stress—whether it be the physical strain from training, mental overwork, or emotional exhaustion—is stress. All forms of stress strain your nervous system and impair proper recovery. Establishing your unique baseline, monitoring trends over time, and contextualizing recovery metrics is essential.
In my next and final post on a proper recovery monitoring strategy, I will suggest some of the best technologies and validated instruments to get started.