THE JUICE ON JUICING
Feel like you’re drowning in a flood of claims and counter-claims about the latest trendy juices? Here we sort the pith from the sweet, sweet nectar of truthiness.
JUICES: GOOD OR EVIL?
Fruit juices have long been considered “healthy” but recently juices (particularly 100% fruit juices) have come under attack for their high sugar content, which is comparable to sodas.
Does that make them bad? Not really. Here are some points to consider:
- One glass of juice a day will be a suitable limit for less active people - but athletes have higher carbohydrate needs.
- Fresh juice with the pulp provides a lot of fiber that will make you feel full and slow down the stream of sugar into the bloodstream.
- Freshly squeezed juice is often touted as a better source of nutrients than commercial juices, but commercially prepared juices that are frozen and refrigerated properly are only slightly lower in nutrients than fresh juice.
- Choose vegetable juices, or mix vegetable juice with a little fruit juice. Vegetables tend to be richer sources of many vitamins and minerals compared to fruits, plus most veggies have a tiny fraction of the sugar in fruits.
As with many things in nutrition, there is a time, place and amount in moderation for everything – including juice. Here are our picks of juices for different purposes.
Choose a “daily juice” that will provide a wide spectrum of vitamins and minerals. Our pick is one with a mix of green leafy vegetables (e.g. spinach, chard, kale, parsley, lettuce) that will be rich in iron and magnesium. Most Americans do not get the 400 mg of magnesium that’s recommended daily – and for athletes especially this mineral is vital for energy production, plus it keeps muscle and nerve function strong, maintains bone health, and boosts the immune system. Mix with some melon for sweetness. If you want a commercially available juice, try pomegranate juice, rated by Web MD as the juice with ‘the biggest nutritional payoff per sip’.
The sugar content of fruit juice is generally too high to be recommended for drinking during a moderate-high intensity workout or for rehydrating immediately afterwards. A drink too high in carbohydrate can cause intestinal cramps or stitches, plus the body doesn’t use fructose as well as the combination of sugars in a regular sport drink. There is also the problem that the acidity of some fruits (e.g. citrus fruits) can make people feel uncomfortable while they’re active. However, if you dilute fruit juice (1/3 juice, 2/3 water), you will have a natural alternative to sports drink that will have a similar level of carbohydrate (6-8%). Choose a low-acid juice that is pulp free, e.g. apple, apricot, or watermelon.
REDUCE SORENESS AND FATIGUE
For as long as I can remember, sliced watermelon has popped up at fun runs and sports days – it turns out we were onto something. Watermelon contains the amino acid L-citrulline, which helps relieve exercise-induced muscles soreness, according to a 2013 study. The study found cyclists who drank 17 ounces of fresh watermelon juice one hour before an intense interval training session had less post-training soreness. We also know that L-citrulline has the ability to convert into nitric oxide (see beet juice, below) for elevated performance in endurance events.
Dark tart cherry juice is another natural protector against the effects of brutally intense workouts. This polyphenol-rich juice reduces oxidative stress, which damages cellular proteins and membranes leading to systemic inflammation, fatigue, and injury.
One study found marathon runners who drank 12 ounces of cherry juice twice daily a week prior to the race and on race day experienced less post-race muscle soreness and fatigue versus those who took a placebo. Tart cherry juice may also improve your sleep because it is rich in melatonin, a hormone that helps regulate sleep cycles. One study found that drinking 8 ounces once in the morning and again two hours before bed for 14 days provided moderate improvement in sleep patterns and insomnia.
KICK A CRAMP
Here’s an odd one – pickle juice just might be the best solution for cramps. A study showed that a dose of 2.5 ounces of straight pickle juice relieved cramping 37 percent faster than drinking deionized water, and 45 percent faster than drinking no liquid at all.
Pickle juice is rich in sodium, magnesium and potassium, electrolytes commonly found in the “ade” drinks on the market, but its effect was so fast (within 85 seconds during the study) that it is now believed that it is actually the vinegar in pickle juice that sparks a nerve reflex, which sends out a signal disrupting the misfiring of muscles and therefore stops the cramping.
RECOVERY FROM HIGH INTENSITY TRAINING
Shove off, hip new expensive fruit from the Amazon – the juice of the humble tomato (a fruit usually eaten like a vegetable) turns out to be a cheap, natural recovery drink.
A study showed that subjects who drank tomato juice (rich in the antioxidant lycopene) after vigorous workouts experienced faster muscle recovery and blood-sugar-stabilization than those who drank a typical energy drink. Specifically, it helped improve the body’s lactate dehydrogenase and creatinine kinase responses to anaerobic training, which suggests that this could be a very good option for strength and power athletes post-training.
More and more athletes are moving to the beets. Beet juice has been well studied for the effects of its high inorganic dietary nitrate and the resulting nitric oxide it produces in the body. (For the record, aragula/rocket, spinach, lettuce and radishes all contain a higher nitrate concentration than beets.)
Studies show that the benefits of beet juice are at their best for events that last from five to 30 minutes. The main benefits are the ability to create the same energy while consuming less oxygen, and a higher oxygen supply.
You have to drink a lot of the pink, frothy stuff – most research has been done with the equivalent of 500-600 mL of beet juice consumed 2–2.5 hours before the event. Many athletes experience some gastric distress, plus there are some other interesting effects:
Mark Cavendish ✔ @MarkCavendish 8:27 AM – 14 Jan 2012
Doesn’t matter how often it happens, taking a pee the day after drinking beetroot juice will always freak you out!! #pissingrainbows
Fortunately, concentrated beet juice ‘shots’ are available now, which makes it easier to get the nitrates without so much bulk in the stomach.
Some research (a small study) has indicated that dietary nitric oxide supplementation could improve performance for stop-and-start action found in team sports such as football, basketball, and soccer by ‘facilitating greater muscle glucose uptake or by better maintaining muscle excitability’.
HYDRATION FOR LONG ENDURANCE
As much as coconut water is built up to be dew from the heavens, it is shot down almost as often. Detractors say the sugar content is too high for an everyday drink, but too low for a sports drink, and that the electrolytes level (especially sodium) is inferior to commercial endurance drinks. However, coconut water has its role, especially for long endurance events (think ultra-marathons, adventure races) where athletes do not rely on any one type of drink and they expect to eat real food during the event. Coconut water may not do everything, but in long events where acute dehydration is a threat and tolerance in the stomach is important, coconut water shines.
Studies show that coconut water enriched with a little sodium replenishes body fluids better than water and as well as a sports drink, but showed a better fluid tolerance than both. Coconut water can also have 15 times the amount of potassium found in a standard sports drink. Potassium is very important for endurance athletes (hence the cravings for bananas and potatoes), plus most Americans don’t get enough potassium in their diets because they don’t eat enough fruits, vegetables, or dairy.
We’ve also witnessed ultra-runners with Type 1 diabetes who favor coconut water over the more sugar-rich sports drinks. There may be more to this – a study in 2012 indicated that coconut water reduced hyperglycemia and oxidative stress in rats with alloxan-induced diabetes (similar to Type 1 diabetes in humans).