Master Class: The Science of Ageing
Chronological vs Physiological time
None of us are getting younger??…….This could be more commonly regarded as a false statement now. Even as chronological time ticks by, huge advances in the practice of exercise physiology and application of strength and endurance interventions are now ‘demonstrably’ able to reverse diseased or declining physiological states; obesity, type II diabetes, cardiovascular and a plethora of other disorders commonly associated with ageing as exercise ‘without any doubt’ has more benefit than synthetic pharmaceutical intervention, read more here.
Improving, i.e. reducing the metabolic age of an individual has not been unheard of….so the big question remains, will we ever be able to reverse the aging process? My answer is…we can do it already, but it will never be available in pill form unless we can molecularise motivation and determination to overide the central govenor! (I’m thinking along the lines of the film/series Limitless here). ‘Hang on!’ I hear some say…..while hormone replacement therapy and growth hormones can have beneficial effects within a scenario of a clinical imbalance (e.g. a pituitary disorder), they generally are associated with some degree of risk and negative effects, commonly teratoma (germ cell derived cancers). So not a viable answer for healthy individuals wanting to ‘regenerate’. Stem cell technology could well be a viable avenue of tissue and organ repair in athletes, stimulating our stem cells to regenerate our bodies could happen and is happening.
More naturally, all we need to do is ‘cheat’ chronological time and tune in to our biological clocks. Tinkering with these may enhance our longevity and quality of life, medically termed compression of morbidity. Improving or maintaining our ability to function as humans, and even more desirable as exceptional athletes well in to our late decades. Increasingly greater athletic achievements are being made by from septuagenarians to centenarians in running and cycling alike, with multiple cases of successfully compressed aging and maintained athleticism.
Deterioration or disuse?
Understanding the reversal of the deterioration of the human body could be best explained in the elderly population and how performance is lost with disuse or organ/tissue decline. Studying master athletes have resulted in exceptional strength and endurance strategies to alter the biological clock and functional ability so atheletes remain competitive and delay performance loss. One thing is for sure, maintaining full capacity requires pushing the body at a high intensity to keep everything in functioning at full potential. Biological life itself is non-linear, we don’t age in a uniform fashion, but respond to disuse, or stressful events or environmental influences which accumulate their effects on our physical being, ultimately resulting in a decline.
If we can tap in to that non-linearity and prevent the accelerated phases, inflammation, poor diets and loss of strength then we can smooth out the peaks and troughs, just like pacing on the bike, the closer we stick to a threshold intensity the less like we are to burn-up and fall short of our goals. In a nutshell live a higher quality life according the biological ‘laws’ at work, which dictate the micro-scale function of gene expression, enzyme kinetics and muscle metabolism through to macro-scale function and organ recovery and adaptation to meet their genetic potential.
One thing we should get straight before I delve into the training recommendations that masters athletes can use to prevent performance losses, is that physical capacity declines are only apparently associated with organ/ physiological deterioration at certain typical ages, it is more likely disuse and failure to perform a required intensity training which contributes to this observed loss of performance. This is commonly referred to as aging, but the simple matter is, if you don’t use it…you lose it! Master athletes tend to reduce training even when they attempt not to do so, many life factors come in to play. Altered training means slower long distance, less interval or power training. Confusingly, it is difficult to distinguish the affects of acute/ de-conditioning when studying life-long changes in physiological function and performance. The factors are complex and inter-related. For instance aches and pains or osteo-arthritis may only allow for a partial-recruitment of all motor-neurones due to lower motivation, and not achieving full effort due to joint problems.
Decline in maximum heart-rate (6-10 bpm per decade), ability to stay hydrated due to an altered thirst mechanism and kidney function, loss of anaerobic and aerobic capacity (VO2peak) are some of the main physiological problems master athletes face. A reduced stroke volume of the heart and less sensitive B-adrenergic stimulation from loss of fast-twitch glycolytic fibres are seen. VO2peak has notoriously been reported to diminish at a rate of approximately 9% per decade after the age of 30. This lower VO2peak can explain how proportional shift in percentage utilisation of VO2max (Lactate threshold) increases blood acidity which can result in breathlessness and the drive to expel more carbon dioxide under aerobic stress. Also, due to fewer lactate tolerant muscle fibers there is reduced removal of lactate, reducing threshold power.
Sarcopenia – Quality muscle mass gain as a primary objective
Sarcopenia, the medical term for the functional loss of muscle from disuse or disease, is a common cause of loss of performance capacity within older athletes, and is commonly replaced by greater fat deposits as can be seen in the featured post image showing the difference in the cross-sectional area of the thigh between a 25 year-old elite triathlete (left) and a 60 year old elite triathlete (right). The maximal heart rate also drops in older cyclists as stated, but there seems to be a compensatory increase in muscular efficiency and hence endurance capability from a proportional shift to slow-oxidative fibers and oxidative-enzymatic composition, meaning cycling economy is increased and can explain good performance besides a lower VO2max. This reduced aerobic capacity is probably a result of both lost lean mass and compromised cardio-respiratory exchange and delivery of oxygen from a reduced tidal volume of the lungs, although high levels of physical activity and cross-training including running may maintain the efficiency of the lungs for years. Therefore, training should predominantly focus on the muscle oxidative capacity to maximise any unresponsive limitations.
Like all athletes, aging masters both male and female require focused and structured training to achieve a realistic performance gain based on previous seasons. In general, hours per week of training should last between 10-13hrs, with the highest volume at 15hrs. No more than 500hrs a year is recommended.
Objective and pragmatic goals are essential, but keeping it simple with a competition calendar and benchmark physiological testing such as critical power and lactate threshold profiling to measure progress. Focus of training is ideally anaerobic capacity, neuromuscular power, sprints, attacking and hills as master athletes commonly lose this aspects of their functional physiology. Hence why many texts suggest that a focus duration of intensity should be both 6minutes and 60minutes for optimal conditioning.
Further, rehearsing race practice is necessary throughout the build periods, but recovery is a critical limitation to the quality of workout sessions, both after long rides and within interval sessions, extrinsically and intrinsically. Conditioning the lactate system is part of the recovery necessary from hill-repetitions, and the tolerance to lactate as part of the anaerobic system and loss of quality lean muscle mass from the major cycling movers, the quads, gluts and calf muscles.
The endurance prescription should be fine-tuned as 3-week meso-cycles, incorporating a rest week after every 2 weeks build, as recovery allows adaptation and compensation to improve performance through biochemical changes in the muscles. There is a tendency to fine-tune build and recovery cycles, as reflected by chronic and acute training load constants to facilitate periodisation.
A 14 day on/ 5 day off or 15 day on/ 6 day off recovery cycle seems to fit many master athletes preparing for competition. Monitoring training closely is very important, so volume can be reduced if over-training too frequently.
To reverse sarcopenia or prevent further loss, periodised weight training with these maximum strength sessions should progress to a power phase with lighter loads but higher reps, which is more specific conditioning for cycling and directly returns performance gains. However some older athletes may show anabolic resistance, meaning that they are unable to develop lean muscle mass possibly due to low testosterone levels. As previously stated in The Science of Protein post, as the catabolic effects of endurance exercise promote the loss of nitrogen in urine, known as protein accretion. Correct nutrition facilitates lean mass development by maintaining a positive protein balance to stimulate muscle protein synthesis to its full potential for repair and growth. Alkaline foods are known to balance nitrogen loss, whereas acidic foods will draw nitrogen from the body. See here for a list of acidic/alkaline foods.
Strength training and injury prevention
Resistance sessions for developing strength are also critical especially in the early stages of a programme, the general conditioning phase of a programme as muscle loss may have already occurred or the individual is prone to losing mass too easily or prone to injury. Injury prevention is desirable in master athletes, as the hamstrings/ knee ligaments or anterior cruciate ligament (running) can be injured if there is a poor daily history of muscle activation. For optimal performance and to minimise injury, a balance of strength between the agonist and antagonist muscles is recommended. One, preferably two sessions a week when endurance training volume is low will help higher quality muscle foundations, and quality of muscle- maximal force per mass, that can transfer across to cycling specific endurance, anaerobic power/ endurance and sprint/ hill attacks. Maximum strength sessions with weight session should also be supplemented with speed transference, high cadence sessions and force on hills. All with adequate recovery, less than 90 minutes on the turbo trainer and avoiding too many training rides, whilst monitoring fatigue (careful use of the Performance Manager Chart on Training peaks and the actual settings for ATL/CTL constants are extremely beneficial).
Intensity and recovery, doing it right.
Once strength work is scaled back, endurance ‘road’ sessions can become more challenging, with force and muscular endurance being more intense, with speed skills and cadence focus to avoid reversion to low-cadence pedalling. Stretching after every workout and biomechanical flexibility should be maintained to help this, and become the most flexible ever.
After more intense endurance training sessions and racing, a re-introduction of strength maintenance resistance session in the gym once per week will help stimulate optimal neuromuscular firing patterns. A further power phase build session is sometimes warranted if the individual loses lean mass easily during the peak event phase, or over-trains.
A structured micro-cycle of interval sessions, sprints, more focus on anaerobic power is required at high intensity to maintain physical performance, although long distance endurance is more easily developed if that athlete has a history of cycling and experience. Prolonged intense training allows masters to surpass the performance capabilities of the majority of the younger population. In contrast, younger athletes may make better performances than older individuals because of improved training methods, better nutrition, social attitudes and strategies in competition.
Many older athletes improve their individual fitness through the years by training harder and smarter, so age does not necessarily need to be related with worse performance. So just be aware of ‘biological time’ when planning your training sessions.