There are many angles on the topic of ageing well, but the angle I am taking here is, of course, associated with health and fitness. In particular, the focus of this article is the importance of building and maintaining your muscle and strength in to your old age.
Sarcopenia is the process of losing muscle mass as you age. It can affect your health and your quality of life. As you will see, there are steps you can take to slow sarcopenia but first, let’s look at why you should take those steps.
Why muscle is important
Nobody looks forward to meeting their maker or even to ageing. At least if we have to age we should try to make our later years as enjoyable and fulfilling as possible and be able to do all the activities we want to do.
To this end, retaining your muscle and functional ability is critical. If you don’t then you could find your lifestyle restricted because you are too frail, too unfit, or too incapable.
If you stay strong you will also be more resilient to trips and falls and, in general, to injury. You’ll be able to avoid the detrimental effect of enforced inactivity or, worse, a permanent disability.
Maintaining your muscle will help you stay upright, maintain good posture and look younger than your years.
In addition to these more tangible benefits, there is a role that muscle has on one’s resilience, one’s ability to bounce back from injury or illness. This is painfully pertinent to events in my life only this week. There are a number of health benefits to maintaining muscle. The body has a constant need for amino acids derived from protein. Muscle is the body’s primary reservoir of amino acids and is vital for maintaining health and function in the absence of dietary amino acids. Muscle helps recovery from disease and injury which would otherwise be hindered by sarcopenia. Without sufficient muscle, a prolonged period of bed rest can leave someone too frail the function. I have witnessed this outcome myself.
And as if all these things weren’t compelling enough, muscle tissue also has a positive effect on metabolism and metabolic health, helping you stay healthy and keep your body fat in check.
So, for a long, healthy and active life, it’s important that you take all the steps possible to preserve or build muscle.
Before we look at how to preserve your muscle, here’s a quick summary of protein turnover in the muscles.
Muscle protein synthesis (MPS) and muscle protein breakdown (MPB)
The body has a constant need for amino acids, the building blocks of protein. It uses amino acids for cell maintenance and replication, for skin, hair and nails, for carrier proteins and so on. The digestive tract has a high cell turnover and requires a constant supply of amino acids to replenish those cells. There is an increased demand for amino acids in times of stress or injury. The liver uses amino acids for gluconeogenesis – the manufacture of glucose.
Muscle is the primary source of amino acids in the absence of dietary protein. If the body has a need for amino acids and they are not available in the bloodstream, then net Muscle Protein Breakdown (MPB) will occur. If a stimulus for muscle growth has been provided and the body is supplied via the diet with adequate quantities of amino acids, then Muscle Protein Synthesis (MPS) will predominate. In reality both processes take place all the time, but one will predominate over the other depending on various conditions.
Now let’s look at ways in which you can preserve or build muscle.
1. Get enough protein
What is enough protein? There are various figures you will find if you look into it. For example
- The UK Government has issued recommendations suggesting 55g protein per day is a sufficient amount to maintain optimal health. They also suggest 9% of total calories from protein. These two figures are in line for the average male. 55g is slightly high for females but they give the higher figure to cover sufficiency for everyone.
- The US Government has issued guidelines suggesting a Recommended Daily Allowance (RDA) of 56g protein per day for males, 46g per day for females. They also suggest the minimum of the acceptable macronutrient distribution ranges (AMDR) is 10% of calories from protein. Again, this is in line with the RDA. Interestingly, the AMDR goes from 10% of total calories to 35% of total calories as an acceptable healthy range. The upper limit of the range corresponds to around 220g protein per day for a typical male.
- The US RDA corresponds to 0.8g protein per kg of bodyweight for a 70kg person. Remember this is a minimum number to maintain health. Studies have suggested figures more like 1.2g per kg of bodyweight and still other studies have suggested up to 1.5kg is appropriate for older individuals to help minimise sarcopenia.
- An often quoted figure for the maximum amount of protein required for muscle growth is 2.2g per kg of lean bodyweight. This corresponds to about 125g protein per day for a 70kg male with healthy body fat levels and around 100g for a healthy woman. More generally, protein grammes corresponding to 2.2g per kg lean bodyweight will depend on the amount of lean tissue a person has. For example, I set my own number higher than 125g because I carry more muscle than average. Taller people will need more protein as they weigh more and have more lean bodyweight than average. Above 2.2g per kg of lean bodyweight, no more muscle growth will occur. This number is in the middle of the US AMDR and so seems a reasonable number to set for optimal protein intake. As you’ll see below, there are reasons why you might take your protein intake higher than that but, in terms of muscle growth, more than that will have no additional benefit – we are better off using our calorie allowance for other macronutrients which have other benefits.
So, in summary, consume at least 56g protein per day but less than 220g. Setting your protein intake at around 125g per day (100g for women) might be a good amount for optimising muscle growth / maintenance and maintaining optimal health, particularly as you get older. If you are taller, have more muscle, train hard or are recovering from trauma, illness or injury, you may need more. As you’ll see, there are reasons why you might have more than this, but this is a good starting point.
2. Get around 25g protein per feed
The body responds to a protein feed by stimulating MPS. The amino acid leucine is the key amino acid component of protein that directly stimulates MPS.
Studies have shown that greater than 20g protein and greater than 2.2g leucine in a feed will optimally stimulate MPS.
Ageing can bring on anabolic resistance. That means the body responds less well to a protein feed and the levels of MPS are not as high. There are two ways to combat this. First, because anabolic resistance raises the threshold at which MPS occurs, increasing the protein intake at each feed will help to compensate for this. Second, exercise, particularly weight training, helps to lower the threshold for MPS to take place.
It has been suggested that the elderly should get at least 25g protein per feed to combat anabolic resistance and minimise sarcopenia.
Note that the higher the leucine content of your chosen protein the better the MPS response. Most animal based proteins are good choices for complete proteins (containing all 9 essential amino acids) and leucine content: meat, poultry, fish, dairy, eggs, whey, casein. For vegetarians, appropriate food combining will help to produce complete proteins and optimise leucine content.
3. Spread protein intake out
MPS is maximally stimulated 60-90 minutes after a meal and then drops off. If more protein is supplied at this point it does not further stimulate MPS. The body needs to reset before MPS will occur again.
What that means is there is no point in having a huge protein feed in the hope of stimulating a huge burst of MPS. For optimising MPS you are better off having multiple feeds of at least 20g protein – more if you are elderly – spread out over the day, with a sufficient gap to reset the body’s MPS response to protein intake.
So what would this look like in terms of a day’s eating? For men this might mean 5 feeds each containing 25g or protein. For women it could be 5 feeds each containing 20g protein or 4 feeds each containing 25g protein. Leaving a 3 to 4 hour gap between feeds should enable a reset of the body’s MPS response to protein. This is a recently recommended approach for older adults.
4. Don’t go low carb
There’s a misconception that carbs make you fat. They don’t. Only calorie surplus makes you fat. In fact a surplus of calories form carbs tends to rev the metabolism and get burned off whereas a surplus of calories from fat just makes you fat.
So why are carbs good?
First of all, MPS seems to be better stimulated when the muscle cell’s energy charge is greater. If the muscle’s energy reserves – mostly carbohydrate in the form of glycogen – are topped up then muscle hypertrophy occurs more readily, perhaps because there are energy reserves available for MPS’s relatively high energy demand.
Second, carbohydrates produce by far the best insulin response of all the macronutrients. Insulin helps to drive nutrients, including amino acids, into the muscle cells, thereby helping to provide the raw ingredients and stimulus for MPS.
Providing fast digesting carbohydrates and protein immediately after exercise is a great way to top up the muscle’s energy reserves and kick start MPS.
At all other times choose slow digesting unrefined carbohydrates to keep blood sugar levels in check, avoid cravings and provide a more constant energy supply.
5. Supplement with leucine
Leucine is the most important amino acid for MPS and directly stimulates it. The amount of protein required to stimulate MPS is driven by the leucine content. Foods with a higher leucine content, such as whey, will stimulate MPS more readily and with a lower total protein amount.
As you age you develop anabolic resistance which means it is harder to stimulate MPS. However, this can be partially overcome either my consuming more protein per feed so that the overall leucine content is increased, or by supplementing with leucine.
You can buy pure leucine but the most commonly available form of leucine comes in the form of branched chain amino acid (BCAA) supplements, which have been around for a lot longer. The BCAAs – leucine, isoleucine, valine – usually come in a 2:1:1 ratio in both powder and tablet form. Tablets are convenient but you may need to grind them for best absorption. Powder will get readily absorbed, but needs to be mixed with liquid, which is less convenient. Either way, they don’t taste great but, for me at least, it’s a means to an end so I just get on with it.
6. Perform resistance training
The most common form of resistance training is with weights. Weight training has a bad reputation, often associated with vanity and steroid abuse. It shouldn’t be about either of those things but it should be a mainstay of your health and fitness regime. I have written before about the benefits of weight training. As well as those benefits, there are a number of points that relate specifically to MPS and ageing:
- Weight training provides a stimulus for MPS. The anabolic effects are proportional to the resistance and intensity so you’ll need to put the effort in for best results.
- A sedentary lifestyle or a prolonged period of bed rest can cause muscle loss and increased anabolic resistance. Resistance training reverses that anabolic resistance.
- Weight training increases the response to amino acids, and MPS is increased as a result.
- Weight training lowers the threshold at which protein stimulates MPS, so that overall protein intakes don’t need to be so high for each meal.
- It is important to consume protein immediately after weight training. Delaying it by as little as 2 hours may cause you to lose muscle mass. A protein high in essential amino acids is best. 25g of a quality protein should maximally stimulate MPS. Whey is a good choice.
I would say this, but if you’ve never weight trained before then you should get a coach. Too many people go to a gym, get shown round once and then left to their own devices. They don’t know what to do, how to do it, how it benefits them or what they should be aiming to achieve. A coach will teach you the exercises, explain what they are for and which muscles they work, create a plan, set goals, motivate and so on. A coach is often the difference between success and failure.
So there you have it: six things you can do to preserve – or build – your muscle as you get older. Build these into your life and you stand a much better chance of having a long and active life.
Before I close this article, it’s worth mentioning some other points about the approach outlined above:
- Protein tends to keep you full for longer. It takes energy to digest and generally is associated with improved satiety. If you consume a good amount of protein with each feed and spread your calorie intake out over the day then you are far less likely to feel hungry and overeat. Eating in this way is a good approach if you’re looking to lose weight. This is one reason why you might eat more protein than suggested above.
- Another reason you might eat more protein is if you want to make sure you are compensating for anabolic resistance as you age. Ideally you will weight train and get plenty of complete protein with essential amino acids but if you’re laid up or have enforced bed rest, then an increased protein intake will minimise sarcopenia.
- There is an association between a higher protein intake and increased bone mass. If you’re not doing any weight bearing exercise then you may want to consume more protein.
- This approach isn’t just for the elderly. If you’re young and looking to put on muscle, even if you’re a bodybuilder, this approach will be highly effective. If you’re trying to gain or preserve muscle whilst you lose weight, then this approach will also be highly effective, enabling you to build muscle and lose fat at the same time.
Finally, I want to say that there is plenty of information on the internet if you want to find out more. All I have done is trawl websites looking for evidence and confirmation and presented it to you in a concise and digestible format. This isn’t a scientific paper, so I haven’t been rigorous with references, but I wanted to include enough for you to see this approach isn’t based on pseudo-science or speculation. I’m not pretending I have studied each reference in great detail. I’m just saying ‘look, someone has done a study on this and drawn a conclusion based on proper science’. I’ve taken the pertinent conclusions from those studies to derive an approach that I know works, because we use it to great effect with our clients.
If you’d like some more information about how we structure our programmes or if you have any questions please just drop me an email and I’ll be happy to help.