Sunlight: More than Vitamin D

by Gabe Mirkin, M.D.

For many years I have offered my opinion that sunlight provides benefits that are not gained just from taking vitamin D pills. Recent research is confirming that opinion, and many scientists now believe that low vitamin D blood levels are only a marker for not getting enough sunlight.

People who get little sunlight are at increased risk for heart attacks, strokes, several types of cancers, infections, bone fractures, diabetes, obesity, depression, auto-immune diseases and other diseases that can cause premature death (J Intern Med, Oct 2016;280(4):375-87), yet the increased risks for these diseases are not reduced by taking vitamin D pills:

• Dr. JoAnn Manson and her associates at Harvard Medical School showed that giving 2000 IU of vitamin D3/day and one gram/day of omega-3 fatty acids for five years to 25,871 U.S. men and women 50 years of age or older did nothing to reduce deaths from heart attacks, strokes, or cancers of the breast, prostate, colon or rectum (N Engl J Med, Jan 3, 2019;380:33-44).

• A study that followed 217,244 Danish people for up to 10 years found that vitamin D did not protect them from developing cancers. Higher blood levels of hydroxy vitamin D were not associated with protection from breast, colo-rectal, urinary, ovarian or uterine cancers, and were associated with increased risk for non-melanoma skin cancers, melanoma, prostate and blood cancers, but a reduced incidence of lung cancer (International Journal of Cancer, Jan 9, 2019).

• The most recognized function of vitamin D is to strengthen bones, yet taking up to 48,000 IU of vitamin D per month for a year did not cause any increase in bone density in 379 men and women over 70 (The American Journal of Clinical Nutrition, Jan 8, 2019).

• Daily supplementation with 4000 IU of vitamin D3 for three years did not improve heart attack risk markers for 161 patients in heart failure (Annals of Nutr and Metab, Dec 17, 2018).

• Many other major controlled studies have also shown lack of benefit from vitamin D pills. A review of 290 prospective studies and 172 randomized trials of the effects of vitamin D pills on disease and disease markers in people aged 18 years or older showed that higher blood levels of hydroxy vitamin D are not associated with a lowered risk for diseases including cancers and that giving higher doses of vitamin D (>20 mg/ or >800 IU/day) to people with lower blood levels of vitamin D did not significantly reduce their chances of developing these diseases (The Lancet Diabetes and Endocrinology, Jan 1, 2014;2(1):76-89). See my recent report, Do You Need Vitamin D Pills?

Other Functions of Sunlight

Certainly sunlight causes the skin to manufacture vitamin D, but it also causes the skin to make large amounts of nitric oxide (J Invest Dermatol, Jul 2014;134(7):1839-1846). This nitric oxide can lower or prevent high blood pressure (Curr Opin Nephrol Hypertens, Jan 2016;25(1):11-15). Exposing the skin to 30 minutes of summer sunlight caused nitric oxide levels to go up and high blood pressure to go down. High blood pressure leads to heart attacks, strokes, and arteriosclerosis, so it may be more important to worry about getting enough sunlight even if sun exposure increases the number of skin cancers. Heart attacks kill 100 times as many North Americans each year as skin cancer does.

People who get ample sunlight are less likely to suffer diabetes (Diabetes Res Clin Pract, Oct 2010;90(1):109-14). A study of sunlight exposure in mice showed that it prevented obesity and metabolic syndrome independent of vitamin D in mice fed a high-fat diet (Diabetes, Nov 2014;63(11):3759-69). Another study in mice showed that ultraviolet light suppressed weight gain, glucose intolerance and insulin resistance, and lowered blood levels of fasting insulin, glucose and cholesterol, and that vitamin D pills did not produce these benefits (Int J Environ Res Public Health, Oct 2016;13(10):999).

Exposure to sunlight also helps to prevent infections including tuberculosis (PLoS ONE, 2013;8:999), increases cancer survival (Int. J. Cancer, 2006;119:1530-1536), and lowers cholesterol (QJM, Aug 1996;89(8):579-89). Sunlight converts squalene in the skin to both cholesterol and vitamin D, so sunlight may lower cholesterol by shifting squalene conversion to vitamin D, rather than to cholesterol.

Avoiding Skin Cancers

It is firmly established that excessive sunlight exposure causes skin cancers, so any recommendation for increasing sunlight exposure must be accompanied by an extensive list of precautions.
• The people who are most susceptible to skin cancer are those with the lightest skin pigments. It is likely that African Americans are at increased risk for diabetes and heart attacks specifically because of their darker skins and they may need, and can safely tolerate, larger doses of sunlight exposure.
• People who have very light colored skin are at high risk for skin cancers from sunlight and should limit their exposure to sunlight. It takes only a few minutes of exposure of a small area of skin to reap the benefits of sunlight.
• Protect the areas of your skin that have received the most exposure over your lifetime. For most people this will be the face and lower arms. Wear a hat and long sleeves, or use sunscreens to protect these areas. Target your sun exposure to less-damaged areas such as your legs and expose them only for short periods of time. Use clothing and/or sunscreens for any activity that keeps you in the sun for more than about 15 minutes.

Cautions About Sunscreens

The most effective protection for your skin is a roof, next are clothes and the least effective are sunscreens. Anything that rubs your skin or causes heavy sweating can remove enough of your sunscreen to lose its protection. Apply enough sunscreen so you can see it on your skin, and re-apply often.

Several common sunscreen ingredients may be more harmful than beneficial. For example, oxybenzone is an endocrine disrupter (Environ Health Perspect, 2001;109(3):239-44) that may increase cancer risk (J Cosmet Dermatol, Feb 2018;17(1):15-19). At this time, micronized zinc oxide and titanium dioxide appear to be safe and effective. For more on sunscreens see: Sunscreens Only Partially Block the Sun’s Rays

Posted on January 24, 2019 .

Goal Setting

7 Keys to Effective Goal Setting

https://www.roadbikerider.com/7-keys-to-effective-goal-setting/

By Coach John Hughes

“If you don’t know where you are going, you’ll end up someplace else.” Yogi Berra.

We often set goals for the year ahead at New Year’s. However, only about 10% of the people who make New Year’s resolutions actually keep them! Here are seven tips on how to get to where you want to go instead of ending up somewhere else.

My 2018 Goals and Successes Reaching Them

Last January 26th I fell off a ladder while putting chairs in the rafters of our garage. I only fell about five feet but it was enough to fracture my ankle. The surgeon put in four screws to stabilize it. Then they strapped my foot into a surgical boot and told me I shouldn’t put any weight on it for six long weeks.


To keep from sinking into a funk I decided my goal would be to ride up to Jamestown, CO (6,926 ft.) by the end of 2018. The climb isn’t tough – 1,342 ft. in 8.4 miles – but it is continuous. The goal was very effective. Here’s why:

1. High priority motivating goal: I thought about many possible goals and picked just one high priority goal for my comeback. My goal was very important to me. Achieving it would signify my comeback from my injury. Focusing on one personally important goal would motivate me for the months ahead.

My goal was a S. M. A. R. T. goal:

2. Specific: My goal wasn’t just to recover from my injury. It was to ride to Jamestown.

3. Measurable: I would know that I’d reached my goal when I arrived at the Mercentile the only business is Jamestown, population 269.

4. Achievable: I set a goal that I could achieve if I trained effectively. Importantly achieving the goal was within my control. It wasn’t dependent on the weather or other riders, factors outside my control.

5. Realistic: My family plans and coaching commitments are important and also time-consuming. Given the available time to ride it was a realistic goal.

6. Time oriented: My goal was to ride to Jamestown in 2018.

7. Planned: I had a simple, measurable plan:

I. Ride 2.5 miles up the canyon toward Jamestown to Buchanan park. I chose this because when I got tired on each ride it was downhill back to my car.
II. Ride up the canyon to the park, stop to rest and eat a snack, and then ride another 2.5 miles up to the junction of James and Left Hand Canyons.
III. Ride up to the park, take a rest break, continue up to the junction, stop again and then complete my ride to the Merc.

The first six weeks after surgery were tough. I had to wear the damn boot 24 hours a day including while taking a shower. At night I had to wear the boot and keep my foot elevated to prevent swelling. While lying on the coach watching the winter Olympics I was allowed to take the boot off to do simple strength and flexibility exercises but otherwise wore it 7 X 24.

After six weeks I was allowed to take the boot off for PT to regain flexibility and strength and to swim and walk in a pool for cardio. I set simple objectives and celebrated the achievement of each:

  • March 27, nine weeks after the accident, I was allowed to get on the trainer without putting much weight on my foot and I rode for five whole minutes! I wasn’t allowed to ride outside because my ankle wasn’t fully healed and if I fell I might need more surgery.

  • April 11 I started doing manageable intensity workouts on the trainer.

  • April 18 my ankle was stabilized and the surgeon removed two of the screws.

  • April 27 they finally removed the boot and I could walk normally! I kept up my trainer rides.

  • May 10 I did my first road ride up to Buchanan park.

  • May 14 I made it up to the junction of the Left Hand and Jamestown roads.

  • May 18 I rode all the way up to Jamestown and back!

I set a new goal: ride the 14.2 miles with 4K of climbing up Left Hand Canyon to Ward, CO (9,449 ft.). It’s a continuous climb and the last two miles are 10 – 15%.

  • June 7 I rode from Buchanan park up Left Hand, 8.8 miles and 1,690 ft.

  • July 13 I climbed the last 6.2 miles and 1,380 ft. to Berthoud Pass (11,307 ft. / 3,446 m)

  • August 6 I made it to Ward. The photo shows how exhausted I was.

Build Your Base First

Whatever your goal every roadie should start the year with at least three months of endurance riding. Base training improves:

  1. The endurance of the cycling muscles by increasing the number of mitochondria. The mitochondria are subcellular structures in the muscles where aerobic energy is produced.

  2. The respiratory system, providing more oxygen to the blood supply.

  3. The efficiency of the heart so it can pump more blood to the muscles. Endurance training improves the stroke volume, the amount of blood pumped per heart beat.

  4. The capacity of the liver and muscles to store glycogen from carbohydrates. Your body can store approximately 1800 calories of glycogen. You can exhaust your glycogen stores during several hours of hard riding. Through endurance training you can increase your ability to store glycogen by 20 to 50%!

  5. The capacity to burn fat during long rides. Through endurance training your fuel mix on endurance rides shifts to more fat and less glycogen, sparing your precious glycogen stores. Note that this doesn’t automatically result in weight loss; that is a function of calories in and calories out.

  6. The neuromuscular efficiency of pedaling. Power is a function both of the strength of the muscles and coordinating the firing pattern of the nerves to activate the right muscle fibers at the right time so you go forward with less wasted energy. Early season endurance training is also a great time to work on pedaling with a rounder stroke and being able to spin smoothly at a higher cadence.

  7. The thermoregulatory system by increasing the blood flow to the skin. Your skin is your largest organ and ability to dissipate heat will pay off later in the season.

Goal to Complete a Specific Event(s)

Many roadies start the year by considering multiple interesting and challenging events such as a big club ride, century, brevets, double century, multi-day tour, race, etc. Here’s how to set your goal(s):

1. Decide priorities: Sort your events into three categories by priority:

  • Key event(s): Pick just one or two rides that you will build your year around. These should be “gotta do this ride” not just “this would be an interesting ride.”

  • Training rides: This is where you put your interesting rides to help you prepare for your key event(s).

  • Fun rides: After all, we ride for fun!

Make your event a S. M. A. R. T. goal:

2. Specific: For example, your key event is to ride metric century. You decide you will ride the Wildflower Metric on April 21.

3. Measurable: Your goal is to ride 100K, not 50 miles.

4. Achievable: You’ve done a number of 40 – 50 mile rides and are fit enough to train up for the 100K.

5. Realistic: You estimate it will take 6 – 8 hours a week to train and you can fit these hours into most weeks.

6. Time oriented: You’ll ride the 100K on April 21.

7. Planned: You create a simple plan of alternating weeks with progressively longer and shorter rides. So that you don’t get injured your plan ramps up slowly and you include several one-week breaks from training.

Goal to Improve Performance

You want to improve your cruising speed, power, climbing, endurance, etc. Here’s how to set your goal(s):

1. Decide priorities: improving cruising speed, climbing or endurance each requires a different type of training. After building your endurance base decide you’ll work on power or climbing or cruising speed. Note that climbing better requires more power and that a higher cruising speed requires both more power and better climbing.

Set a S. M. A. R. T. goal for one aspect of performance.

2. Specific: Work on power.

3. Measurable: You don’t need a power meter or a heart rate monitor. Do a baseline time trial and repeat it every four weeks or so. If you go faster you’ve improved your power.

4. Achievable: You have the both the endurance base and the motivation to train harder.

6. Realistic: You can improve your power by doing a couple of hard rides during the week and an endurance ride on the weekend. You can schedule the two hard rides a week knowing that you’ll be very tired after each ride, which could impact your family and work.

6. Time oriented: Starting April 1 you’ll improve your time trial performance by 3% – be conservative – by May 31 so that you can then work on climbing.

7. Planned: You create a simple plan of progressively harder intensity rides. So that you don’t get injured your plan ramps up slowly and you include easier weeks for more recovery.

Tips on Achieving Your Goals

  • Make only a few high-priority resolutions or goals

  • Choose meaningful, motivating goals

  • Prioritize them

  • Make them S.M.A.R.T. goals

  • Write down your goals

  • Post them where you’ll see them every day

  • Tell others about them

  • Develop a simple plan with intermediate objectives

  • Track your progress per the plan

I’m a cross-country skier and my next goal is to ski Lactic Grande before the end of XC ski season sometime in March. Lactic Grande is an expert only trail that climbs to 9,300 ft. and it takes about half a day. I have good cycling fitness, which I now need to turn into skiing endurance and climbing power. I also need to work on my descending skills to get back down without crashing!

What’s your next goal?

Posted on January 3, 2019 .

Anti-Aging: In Your 60s How Fast Do You Lose Fitness?

By Coach John Hughes

My friend and RBR reader Janet wrote, “One way I monitor my level of cycling fitness is by how hard (or easy) a routine ride is. I was off my bike for only 26 days and I could not believe how hard one of my routine routes was, the climbing in particular. I am so glad I did that ride yesterday. It’s basically looking in the mirror. I will now work on getting my fitness back.

“Is there a well-known relationship between how long it takes to build a level of cycling fitness vs. how long it takes to lose it?”

This is an excellent question that applies to all older riders, and the older you are the faster you lose fitness when you stop exercising. Unfortunately it takes a long time to build fitness and you lose it fairly quickly. Your body stays just fit enough to do what you ask it to do. The less you do the more fitness you lose.

Athletic Maturity

How athletically mature a roadie is bears on how fast the rider loses fitness. In my two-part eArticle Cycling Past 60 I develop the concept of athletic maturity and explain how to evaluate your athletic maturity. Based on an individual’s athletic maturity I recommend different exercise programs.

Three factors of athletic maturity are directly relevant to how rapidly you lose fitness:

1. Years riding.
How many years have you been riding: 1-2 years; 3-5 years; 6 or more years? The more years the more athletically mature you are because of a larger endurance base.

2. Miles per year.
How many miles a year do you ride: < 3,000 miles (5,000 km); 3-5,000 miles (5-8,000km), >5,000 miles (8,000 km)? The more miles per year you ride the more consistent you probably are so you lose fitness more slowly.

3. Longest annual ride. 
How long is your longest ride: <50 miles (80 km); 50-100 miles (80-160 km; >100 miles (>160 km)? The longer your big the ride the greater your endurance.

Two other factors of athletic maturity also influence how quickly a roadie’s fitness declines:

4. Leg strength?
How many step-ups can you do with your: body weight; body weight + 10%; body weight +20%? The stronger your legs are the more athletically mature you are.

5. Body weight? 
Based on the Body Mass Index (BMI) how healthy is your weight? Athletically active people have more muscle. Adjusting the BMI for this are you: obese; overweight; normal? The more you have maintained a normal weight the more athletically mature.

The other factors to assess your athletic maturity are upper body strength, flexibility and balance.

How To Reverse The Loss Of Fitness

Use these principles to regain your fitness:

Work on your weakness(es). 
Look at the above five factors. Where are you least athletically mature? Then spend relatively more time working on improving in that area without completely neglecting the other factors. You’ll get better results if you just try to improve one area at a time instead of trying to improve significantly in several areas at once.

Intensity and strength training. 
You lose power and strength faster than you lose endurance. You have two types of muscle fibers: slow twitch fibers, which have great endurance but little power and fast twitch fibers, which have strength and power but much less endurance. The muscle fibers are recruited progressively. As you ride at an easy pace some of your slow twitch fibers are firing. When you start riding a little faster more of your slow twitch fibers start working. When you start riding hard, e.g., climbing up a tough hill, your fast twitch fibers also kick in and your slow twitch fibers keep firing. Because intensity on the bike and strength training cause your fast twitch fibers to work both intensity and strength training are so important. (Slow- and fast-twitch refer to how quickly the muscle fibers contract, not your cadence.)

Consistency throughout the year is critical.
You need to ride almost every week of the year rather than taking a month off from Thanksgiving to Christmas. Why “almost” every week? Because recovery is also very important and you need periodic breaks of about a week or so to refresh physically and mentally. It’s fine to take next mostly off for Thanksgiving with your family and to take Christmas and New Year’s off but stay active in between.

Frequency.
Frequency is more important than volume as you work to slow down the loss of fitness or to regain fitness. In other words you’ll get more benefit riding four days a week for a total of 100 miles than doing one 25-mile ride mid-week and 75 miles on the Saturday.

Activities of daily living also help. 
The more generally active you are the more slowly you lose fitness, e.g., climbing the stairs instead of taking the elevator and walking to the local coffee shop or market instead of driving.

Specificity.
However, staying active throughout the day isn’t sufficient. When you are riding your muscle fibers fire in a specific pattern. Even if you maintain some fitness through activities of daily living but don’t ride much you start to lose your muscle memory. Simply running errands on your bike instead of driving helps to maintain your muscle memory.

Bottom Line

The bad news is that the older you are the faster you lose fitness. The good news is that with an exercise program using the above principles you can reverse that!

Happy Thanksgiving! I appreciate the time all of you take to read my columns and to ask good questions. Each of my clients is doing a short Thanksgiving ride next week without the computer and just thinking about all that he or she has to be thankful for. I suggest you do something like that next week for Thanksgiving too.

My wife and I are avid cross-country skiers and two of our ski areas have a few kilometers of trails open so we’re going to the mountains for Thanksgiving. We’ll take our rock skis, old skis that we don’t mind skiing over the occasional rock.

Posted on November 15, 2018 .