The relationships between golf and health, with multifunctional golf facilities thrown in just for fun

Golf and health

Yesterday I saw the new paper by Murray et al. in the British Journal of Sports Medicine on The relationships between golf and health: a scoping review. The reviewers identified 301 studies on this topic that met their search criteria, and then they summarized the results in terms of:

  • participation
  • golf and physical activity
  • golf and longevity
  • golf and physical health
  • cardiovascular system
  • respiratory system
  • metabolic health
  • cancer risk
  • musculoskeletal health
  • golf and injury
  • golf and mental health/wellness
  • mental health
  • mental wellness

It's a comprehensive review, and if you are interested in this topic, I suggest you read the paper. From the golf and physical activity section, here's the calorie burn and walking distance:

Studies assessing calorie expenditure during golf typically classify golf as a moderate intensity physical activity with energy expenditure of 3.3—8.15 kcal/min, 264—450 kcal/hour, and a total energy expenditure of 531—2467 kcal/18 holes. Golfers walking 18 holes take between 11,245 and 16,667 steps, walking 4—8 miles, while those playing and riding a golf cart accrue 6280 steps or just under 4 miles.

This ties in well with something I've written about before, which is golf and health and multifunctional facilities. In the words of Don Mahaffey, "golf is good for you" but this aspect of golf is often overlooked.

See these posts for more from Don Mahaffey, and from info about STERF's research into multifunctional golf facilities:

A few examples of multifunctional facilities


Weddings and banquets, of course, are common at many facilities. This is a chapel at Club de Golf Escorpión in Valencia.


Use of a practice tee for sports training, at Escorpión.


A football field at El Saler, just to the right of the 8th and 9th holes. This has been used by the Spanish national team and by Valencia CF, among many others.


Birdwatching is a common activity at El Saler, and this sign near the clubhouse shows many of the species one can find in this area.


Many golf facilities have trees or hedges with fruits or nuts. At Golf Costa Brava, the cork oaks are harvested.


Walking, hiking, or biking the Cami Ral will take one right through PGA Catalunya.


Hiking paths at Domaine de Falgos in the Pyrénées start at the golf clubhouse.


The driving range fairway at Domaine de Falgos doubles as a rugby field.


Cool-season grass in a tropical climate

Construction delays and an intensive events calendar have been cited as causes of pitch problems at Singapore’s National Stadium, “adding to the woes of a stadium that has drawn heavy flak for its sandy pitch.”

An editorial in the Straits Times said “Its patchy and sandy pitch thus represents an astonishing lapse that must be addressed swiftly if it is not to count as a national disgrace.” 

This is an interesting technical problem, especially when one learns that the grasses being used in Singapore’s tropical climate are “rye and blue grass.” I presume that these are perennial ryegrass (Lolium perenne) and kentucky bluegrass (Poa pratensis). These species are used in locations where the average annual temperature is less than 16°C. In the two coolest months of the year in tropical Singapore – December and January – the average temperature is 26°C.

Where in Asia does one find these cool-season grasses? In Beijing, Seoul, or Sapporo – in places where it is cooler than Shanghai. Where it is warmer than Shanghai, warm-season grasses are used, and especially when the average annual temperature is more than 20°C, there is almost exclusive use of warm-season grasses. This chart plots a number of world cities by average annual temperature. A check of the turf species forming the base surface on sports fields in those locations will confirm that temperature cutoff point.


The reason cool-season grasses don’t persist in temperatures above those optimal for growth (15 to 24°C for leaves, 10 to 18°C for roots) is because of higher respiration and less net photosynthesis. Grasses make carbohydrates through photosynthesis, and they use carbohydrates through respiration. If more carbohydrates are used than are made, the plant is said to have a negative carbon balance.

DaCosta and Huang describe what happens in their chapter on heat stress physiology and management from Turfgrass: Biology, Use, and Management:

Under prolonged heat stress the imbalance between carbon consumption and carbon production results in the depletion of carbohydrate reserves, which in turn limits the survival of turfgrass.

Rather than construction delays, it would seem that this negative carbon balance, an inevitable result when growing cool-season grasses in a tropical climate, would be an issue with grass performance on the pitch.

I’m not sure if the soil is cooled. I've not read about that in the Straits Times. Based on research with other cool-season grass species, and observations of kentucky bluegrass and ryegrass performance across a range of temperatures, those species would probably provide an acceptable turf in Singapore if the rootzone temperature could be maintained below 22°C. 

The kentucky bluegrass turf at Kashima Stadium in Ibaraki, Japan, grows well during months when the temperatures are cooler than at Singapore; during the 2 hottest summer months at Kashima, when temperatures are similar to Singapore, the grass is weak and uses its carbohydrate reserves accumulated during the 10 other months with suitable temperatures, to survive.

But the average annual temperature in Singapore is more than 26°C, and the rootzone temperature, if a refrigeration system is not being used, would be very similar to the air temperature. So why would rye and blue grass be used? I can guess that it has to do with the amount of light that reaches the pitch. 

There is an extensive roof on the National Stadium. This will restrict the amount of photosynthetic light that reaches the grass. And cool-season grasses generally have a lower light requirement than do warm-season grasses.  

If the rootzone at the stadium were maintained at less than 22°C, the cool-season grasses may have a chance to survive and to perform better than warm-season grasses. That's only because of light requirements for the different types of grass. Cool-season grasses may outperform warm-season grasses with light restriction in tropical temperatures, but only if the rootzone is refrigerated. Based on the performance of the grass so far, it does not appear that the rootzone is cool enough. 

Warm-season grasses thrive in hot weather because their photosynthetic pathway is adapted to efficient carbohydrate production at high temperatures. But warm-season grasses have a higher light requirement, in general, than do cool-season grasses.

The light available for photosynthesis is expressed as a daily light integral (DLI). It is the photons of photosynthetically active radiation striking a surface in one day, expressed in units of moles of photons per square meter per day. I’ve estimated that the average DLI in Singapore, accounting for cloud cover, but assuming there is no shade from trees or buildings or roofs, will be about 35 mol m-2 d-1.

I guess perennial ryegrass and kentucky bluegrass may receive enough light to perform well, assuming the rootzone is cool enough, at a minimum DLI of 20. If the roof at the National Stadium restricts 80% of the natural light from reaching the pitch, then the DLI on the pitch would be about 7. Supplemental lighting could be used to increase the amount of photosynthetically active radiation.  But if the natural light is restricted too much, supplemental lights won’t be able to add enough to the DLI. Supplemental lights, run for 24 consecutive hours, may increase the DLI by about 15 mol m-2 d-1

A quantum meter at Kashima Stadium measures the instantaneous photosynthetic photon flux density; adding together each instantaneous measurement for the course of a day gives the daily light integral (DLI).

With those assumptions – that a DLI of 20 is required, that the roof blocks 80% of the light leaving a DLI without supplemental lighting of 7, and that with supplemental lights on for 24 hours a day, one could get a DLI of 22 – it would seem that it just might be possible to have grass on the pitch. But I don’t know the actual light restriction caused by the roof, or the exact specifications of the supplemental lighting system. 

One can see that the success of the grass on the pitch comes down to a math problem. First, is the temperature of the rootzone cool enough for the species being grown? Second, is the DLI high enough to support the necessary growth and recovery of the grass?

The nual noi variety of manilagrass (Zoysia matrella) is a warm-season grass that may also require a minimum DLI of 20 to produce an acceptable turf. That is, for a warm-season grass, nual noi is relatively tolerant of shade, and in fact has a similar DLI requirement to cool-season grasses.

And perhaps most importantly, for the situation of a venue with an intensive events calendar, it grows rapidly compared to other warm-season grasses. In experiments at Thailand, with grasses given the same fertilizers and grown at a DLI of about 30, nual noi had 52% and 25% greater clipping yield than bermdugrass and seashore paspalum, respectively.

Whether any grass can work in the environment of the National Stadium, and which species it should be, will come down to what temperature the rootzone can be maintained at, and how much light is provided to the pitch. 

3 fine football fields

On the eve of the World Cup, I have three quick things to share about football/soccer. 

Kashima Soccer Stadium, March 2014

1. I've been to two matches at the Kashima Soccer Stadium (this was a venue for World Cup games in 2002) in the past year, one at the end of summer, and one at the beginning of spring. The grass is a mixture of 2 kentucky bluegrass (Poa pratensis) varieties and one hybrid bluegrass variety. In this part of Japan it would be typical to use warm-season grasses on sports fields – summer temperatures are similar to those in Atlanta – and on the surrounding golf courses and lawns, warm season grasses are grown. I've been impressed at just how good the turf is here. Almost all the stadiums in J.1 are bermudagrass, so this pitch at Kashima Stadium is exceptional in being cool-season grass, and exceptional in being maintained to such a high standard. 

2. In the Thai Premier League, one can find matches played on bermudagrass, zoysiagrass, and seashore paspalum. Muangthong United play at the SCG Stadium on the north side of Bangkok, and the pitch here is seashore paspalum.

Seashore paspalum at SCG Stadium in Bangkok, April 2014

To keep the ball moving quickly, water is added at halftime. 

Irrigation at halftime, SCG Stadium

This is the best pitch I've seen in Thailand.

3. If you haven't watched this feel-good story about the amazing Panyee FC in an amazing part of Thailand, take a couple minutes and watch it now. I bet you haven't seen football played like this.

J.League Division 1, Grass Types, and Overseeding

Kashima_cornerOf the 18 clubs in J.League Division 1 this year, just 3 play on cool-season (C3) grass pitches. One of these clubs is Kashima Antlers, and on two recent trips to Japan I had a chance to visit their home ground, Kashima Soccer Stadium, and see their training grounds in Kashima.

The J.League season runs from March to December. With the high temperatures across most of Japan in summer, it is difficult to keep C3 turf alive, let alone in acceptable condition for professional football, so most pitches are C4 hybrid bermudagrass (Cynodon dactylon x C. transvaalensis) overseeded in autumn with perennial ryegrass (Lolium perenne). Kashima Soccer Stadium is unique in having a field of kentucky bluegrass (Poa pratensis) and hybrid texas bluegrass (Poa arachnifera x P. pratensis) for improved heat tolerance.


The stadium and training ground for Kashima Antlers are maintained by I-G-M, and they also maintain the Japan National Training Center in Osaka. When I visited Kashima in early September to meet with Mr. Suzuki and the team from I-G-M, I was impressed with the condition of the pitch. Even at the end of the hot summer, there was still an extensive root system. I also saw the impressive (and invisible until the sprinkler system was turned on) turf-capped sprinklers. 


When I visited again on a game day in mid-October, the turf was even stronger, and was fully recovered from the heat stress of summer.


It is a great atmosphere in the stadium. The Antlers fans came into the stadium more than 4 hours before game time and were cheering loudly before the game had even started.

At the Kashima Antlers training ground, there are three pitches, each being hybrid bermudagrass overseeded with perennial ryegrass. We visited on 19 October, right in the middle of the overseeding process. One field had been overseeded, mown once, and was being painted in advance of use in two days. The second field was being overseeded and topdressed while we visited, and the third field was to be done the last week of October.

The overseeding process at Kashima; a) bermudagrass scalped and spiked, perennial ryegrass spread at 70 g/square meter; b) field topdressed with sand after seeding; c) the field after 1 mowing, about 2 weeks after seeding; d) painting the field 2 days before it will open to the team for practice

In 2013, October is the optimum time to overseed at Kashima. We can identify that time by looking at the temperature-based turfgrass growth potential. The turfgrass growth potential was developed by Wendy Gelernter and Larry Stowell at PACE Turf as a way to improve the success of overseeding. It is also a useful tool for predicting turfgrass nitrogen use.

I calculated the growth potential for C3 and C4 grasses based on temperatures at Kashima from early August to the end of October this year.


The temperature-based turfgrass growth potential from early August to late October 2013, using temperature data from Kashima; the lines on the chart show the average growth potential.

The best time for overseeding is when the C3 growth potential is significantly higher than the C4 growth potential, and when there are still many weeks of a relatively high growth potential for C3 grass to establish. The average C4 growth potential dropped below 0.5 right about 1 October, just as the C3 growth potential was reaching a peak. The optimum time to overseed in these conditions would be in the early part of October, which is just what was done at the Kashima Antlers training ground.

It is interesting to note, at the left side of the chart, just how poor the temperatures are during summer for C3 grass, and how good they are for C4 grass. Seeing those data makes me even more impressed that I-G-M are able to produce such a fine pitch at the stadium. One can understand why almost all the J.League teams play on C4 turf.

How to Prepare an Elephant Polo Ground

When you want to play elephant polo, you surely think of having a well-prepared field. But just six weeks before this year's King's Cup Elephant Polo Tournament, the field needed a lot of work. Minachai Srichanya, the golf course superintendent at nearby Banyan Golf Club, coordinated a volunteer maintenance program to turn the field from this ...

... into this.


What work was done to get such an improvement on this field, situated at an army camp just south of Hua Hin? First, the edge of the field was marked, the grasses (primarily Zoysia matrella) and weeds were mown, and clippings were removed. This work was done by the golf course maintenance staff from Banyan Golf Club, with support from Jebsen & Jessen and The Toro Co.

Mark Mow

Then, fertilizer was spread to stimulate grass growth, and sand topdressing was applied where necessary to smooth the surface.

Then it was just a matter of more mowing, and time, to produce the results for this hotly contested international polo tournament. No word yet on how much soil compaction is caused by polo elephants. More than from ponies, one presumes. 


Photos provided thanks to Banyan Golf Club and the Kings Cup Elephant Polo Tournament.

Turfgrass Performance Data at the Open Championship


The machine I'm operating in the photo above, on the 1st green of the Old Course, is the STRI Trueness Meter. This measuring device, which I mentioned in a previous post, is designed to measure the amount of vertical and horizontal deviation a ball will experience as it rolls across a putting green. In essence, this device measures how smooth the greens are, whereas the stimpmeter measures how fast greens are. Are green speed and surface smoothness positively correlated? Our measurements this week have shown that factors other than smoothness have an effect on speed, at times, so in some cases the smoothness readings are better when the stimpmeter readings have been lower. I discussed the relationship between surface trueness, or smoothness, and the green speed with Dr. Christian Spring of STRI. He says that there is a positive relationship between the two, but that it is not necessarily a causal relationship.

One maintenance technique that improves the smoothness of greens and improves the consistency of smoothness between greens is lightweight rolling. If you haven't been to St. Andrews and the Old Course, you will enjoy the video of the 13th green being rolled this week as the STRI tournament agronomy team approaches to begin collecting performance data on the green. Seeing the roller go across the green gives some indication of the vast size of this putting surface (over 3500 m2).

Richard Windows from STRI and championship agronomist for this Open Championship uses a stimpmeter to measure the green speed of the practice green near the 1st tee (see below). We measure the soil moisture, the green speed, the trueness, and the firmness of the greens, and it is quite useful to have these data. I think, and I will write more about this when I have time, that we should be less concerned about what color the grass is, and should simply focus on the playability/performance data. I often hear phrases about golf course maintenance such as "brown is the new green" or "green is soft" or "lean and mean" or "firm and fast" etc.. But that is irrelevant and is mostly visually descriptive. By some simple collection of data about the playability of the course, it is possible to better describe the playing conditions of the course, and that is more relevant to the game of golf.


Field Renovation for the 2010 World Cup

World_cup_renovationI received this document with three pages of photos of the renovation process for 72 playing fields to be used for the 2010 FIFA World Cup at South Africa next month. Click here or on the photo at right to download the file (2 MB).

Ten fields will be used for the tournament matches, and the remaining fields are for training, as home practice fields for each of the 32 teams in the tournament, and there are even three fields prepared just for the tournament referees. The fields are mostly kikuyugrass, but for the tournament have been overseeded with perennial ryegrass to provide a vibrant green color and some wear resistance during the South African winter. The document about the field preparation is provided by Redexim as much of their equipment was used in the renovation and overseeding of the playing fields.