Which Athlete Ate the Most Nitrates…

A recent blog emphasised the importance of nitrates in our diet. But which vegetable contains the most nitrates and when is the best time to eat them if you want to boost your exercise performance?

Some insight came recently from a balanced crossover research study which looked into whether concentrated beetroot juice (CBJ*) would improve athletic performance by increasing nitric oxide production within their bodies. They took 10 healthy men, split them into a placebo group (P*) and the beetroot group (B*).

*My abbreviations.

Varying amounts (70, 140 and 280 ml) of CBJ were given to the B group over a twenty four hour period. The men were then given six different moderate- to severe-intensity sessions of cycling.

The group consuming 140 and 280 ml of B increased their nitric oxide levels as the CBJ dose was increased, with peak changes occurring at approximately two to three hours after consumption.There were some significant differences between the two groups in terms of athletic performance, with the variations being dependent on the quantity of CBJ consumed, as follows:

  • 70 ml CBJ made no difference between the B group and the P group.
  • 140 and 280 ml CBJ reduced the steady-state oxygen uptake during moderate-intensity exercise by 1.7% and 3.0%, and time-to-task failure (the point of physical exhaustion) was extended by 14% and 12%, respectively, compared with the P group.

Basically, this meant that the P group could manage around eight minutes of intense cycling after drinking their placebo.

After consuming 70 ml CBJ (4 nitrate “units”), the B group were only able to cycle for a few seconds more than the P group. No big deal.

But, but after consuming 140 ml (8 nitrate “units”), the B group were able to cycle for around a whole extra minute. Drinking the 280 ml dose (16 nitrate “units”) didn’t improve performance any further.

So when is the best time to have your beetroot juice?

Whilst people differ in their requirements and absorption rates, it is thought that eating your beet two to three hours before strenuous exercise or athletic competitions is a good rule of thumb.

Were any other health markers affected by the CBJ?

It appears that blood pressure may have been lowered by a small amount with 4 units, but 8 and 16 units were able to produce a 10-point drop in blood pressure – reducing heart attack risk by 25% and stroke risk by 35%.

Okay, so 8 units of nitrate from concentrated beetroot juice does a pretty good job at improving athletic performance, possibly by enhancing vascular function and oxygen absorption…

…but isn’t an extracted and concentrated juice, whether made from fruit or veg, still a processed food?

Indeed it is.

So how else can we get those 8 nitrate units from readily-available and reasonably-priced veg?

Dr Greger shows what goes into his own vegetable smoothie recipe in this video:

Now I know a previous blog explained how chewing nitrates was better than juicing them, since it increases the nitrite available for our endothelial cells to make nitric acid; but it’s far better to cram that veg into your body in the form of Dr Greger’s smoothie than not to eat the veg at all!

A helpful guide to the nitrate content of groups of vegetables was provided as a result of some research by the British Heart Foundation.

The following is a chart that they produced:

Taking into account both the serving size and nitrate concentration, they arranged the foods into three groups:

  • high nitrate – worth 2 nitrate servings
  • medium nitrate – worth 1/2 of a nitrate serving, and
  • low nitrate – worth 1/10 of a nitrate serving

If, however, we’re aiming for the 8 units of nitrates a day, we need to eat a LOT more vegetables than most people are used to eating. It’s suggested that the majority of people people get only around one unit a day.

To end on a possibly surprising note, those eating a completely organic diet may have to eat more vegetables than those eating non-organic.

Why? Simply because research suggests that synthetic nitrogen fertilisers leaves more nitrogen in the vegetables that end up on our tables.

Not everything in the field of nutrition is quite as cut and dried as it may at first appear…


[qsm quiz=4]

 

 


References

Wylie LJ1, Kelly J, Bailey SJ, Blackwell JR, Skiba PF, Winyard PG, Jeukendrup AE, Vanhatalo A, Jones AM. J Appl Physiol (1985). 2013 Aug 1;115(3):325-36. doi: 10.1152/japplphysiol.00372.2013. Epub 2013 May 2.
Beetroot juice and exercise: pharmacodynamic and dose-response relationships.

Lidder S1, Webb AJ. Br J Clin Pharmacol. 2013 Mar;75(3):677-96. doi: 10.1111/j.1365-2125.2012.04420.x.
Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. 

NF Hord, Y Tang, NS Bryan. Am J Clin Nutr. 2009 Jul;90(1):1-10. Food sources of nitrates and nitrites: the physiologic context for potential health benefits.

R Kazimierczak, E Hallmann, J Lipowski, N Drela, A Kowalik, T Püssa, D Matt, A Luik, D Gozdowski, E Rembiałkowska. J Sci Food Agric. 2014 Oct;94(13):2618-29. Beetroot (Beta vulgaris L.) and naturally fermented beetroot juices from organic and conventional production: metabolomics, antioxidant levels and anticancer activity.

V Worthington.  J Altern Complement Med. 2001 Apr;7(2):161-73. Nutritional quality of organic versus conventional fruits, vegetables, and grains.

Szopinska A and Gaweda M.  Journal of Horticultural Research. 2013, 21(1): 107-114. Comparison of Yield and Quality of Red Beet Roots Cultivated Using Conventional, Integrated, And Method.

Physical Exercises for Beginners & Seniors

Time for Exercise

Even if you are on the healthiest diet, exercise is still really important. Here are some suggestions if you are considering starting some regular exercise and want to start flexing those muscles.

There are basically three areas that we will look at:

  1. Stretching exercises
  2. Aerobic exercises
  3. Strength training/load-bearing exercises

1. Stretching exercises

This helps to maintain the range and flexibility that your joints require. A knock-on benefit is that stretching reduces the risk of muscle soreness and injury. You might consider joining a yoga or Pilates class which will help you to increase your stability and core body strength. But you can do all the stretching you need at home. It’s a good idea to make this type of exercise a part of your daily routine.

The following three stretching videos are a good starting point. I would suggest that you build up to all the stretches shown, maybe aiming to be able to do all the stretching exercises by the end of 7 days. Just play the videos, follow their instructions and let them give you the encouragement to continue.

This is a simple introduction to Pilates:

And this is a basic introduction to yoga:

Have a try at the above and see how you get on with the different methods. Some people are happier with one form of stretching than another.

2. Aerobic exercises

You could, of course, just join a local gym and take guidance from an instructor. However, if this is not for you at this stage, maybe consider regular walking, cycling or swimming as a starting point.

You could also consider buying a cross-trainer, exercise bike or running/walking machine. These are excellent ways of being in control of your daily aerobic exercise (not weather-dependant and you don’t need to get dressed up to go out). Increase duration and effort gradually so that your larger muscles can build up and your joints can strengthen without suffering soreness or strain.

Lots of people buy these exercise machines, never use them and end up selling them cheaply on 2nd-hand websites. Maybe that’s where you are best off finding one. You don’t want to be spending lots of money on new machines if you are still unsure that you are going to use them regularly.

Aerobic exercise will benefit your cardiovascular system. Aim to start with 15-20 mins per session, 3 or 4 days a week. Whether walking, cycling, swimming or using running/walking machines, exercise bikes or cross-trainers, ensure that you are able to pass the “talk test” – that is, exercising at a pace which also allows you to have enough spare breath to carry on a conversation.

Once 20 mins seems easy, start to increase exercise time and intensity until you can exercise comfortably for 40 mins without stopping.

3. Strength training

Again, you may wish to simply join your local gym and take advice from an instructor. Alternatively, as with aerobic exercise, you can start by doing all you need in the comfort of your own home.

You will need to purchase a set of dumbbell weights.

Some people prefer this type because they want to be able to vary the weight without having too many dumbbells around the place:

While other people prefer this type, because they are nicer to handle and don’t need to be adjusted in order to vary the weight:

 

Whichever type you get, I would start with no heavier than feels really comfortable for you to lift 8 times at your current strength level. It’s surprising how quickly you will improve as you practice and you’ll be able to lift heavier weights in time as your muscles and joints strengthen. Aim to gradually increase from 8 to 12 repetitions and do your initial weight-bearing exercises every other day for the first week or so, concentrating on different muscle groups each session.

Using dumbbells (or hand weights as they are also called) will improve your strength and posture, as well as maintain your bone strength and density, reduce the risk of lower back injuries and help your body tone up.

The following videos are a good starting point for the beginner:

And for the more adventurous:

All movement matters!

So, even if you’re too busy for your regular workout, find ways of keeping active.

Look for other ways to be in motion:

  • walk up and down stairs instead of taking the lift or escalator
  • walk or cycle instead of using the car whenever possible
  • find a sport or outside activity you enjoy
  • consider teaming up with a friend or a group of friends to exercise with you or share an activity
  • offer to walk dogs – either your friend’s or those at a local dog rescue centre

Remember, research indicates that all those extra steps you take during the day will add up to big health benefits, not just physical but also mental and emotional.


References

Health benefits of physical activity: the evidence – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1402378/

Exercise for Mental Health – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470658/

Health matters: getting every adult active every day – https://www.gov.uk/government/publications/health-matters-getting-every-adult-active-every-day/health-matters-getting-every-adult-active-every-day

A Little Exercise Might Lengthen Life – https://www.nih.gov/news-events/nih-research-matters/little-exercise-might-lengthen-life

Exercise for brain health, study suggests – https://www.ed.ac.uk/news/all-news/exercise-231012

Exercise: 7 benefits of regular physical activity – https://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/exercise/art-20048389