You have prepared yourself for the distance – you have prepared yourself for the climbing, you have prepared yourself for the hours in the saddle but have you prepared yourself for the HEAT? The Cape Epic is a particularly brutal race in the hot summer months of the Western Cape, South Africa when temperatures can soar to the high 30’s (Celsius) and sometimes early 40’s (Celsius). The area has recently experienced an extreme drought in which temperatures reached record highs for extended periods of time. The Cape Epic stage race by nature places a significant strain on participants, riding consecutive days in high temperatures over long, dry and dusty terrain often with long, rough singletrack climbs gaining large altitude (>300m) and offering little breeze or escape from the beating sun. The 2020 event will feature extensively more climbing than in previous years.
Climbing offers additional physiological stress and strain in a stage race and if the weather is HOT then it is essential that the athlete is well trained and has undergone heat acclimatization (HA), specifically the athletes coming from the northern hemisphere winter (approximately 30% of the Absa Cape Epic field) All images supplied by Absa Cape Epic, Nick Muzik & Mark Sampson
image supplied by Absa Cape Epic, Nick Muzik
Why should you Heat Acclimation for the Absa Cape Epic?
It is probably going to be hot for the eight days of the #untamed Cape Epic. Heat will affect your performance. It is intuitive that increased body temperature will ultimately induce strain, impair your endurance performance, and accelerate exhaustion.
image supplied by Absa Cape Epic, Mark Sampson
TIP: Acclimating yourself to heat independent of aerobic physical activity through sauna use induces adaptations that reduce the later strain of your primary aerobic activity. Heat conditioning in a sauna improves your performance during endurance training activities by causing adaptations, such as improved cardiovascular and thermoregulatory mechanisms that reduce the negative effects associated with elevations in core body temperature. This helps optimize your body for subsequent exposures to heat (from metabolic activities) during your next big race or even your next workout. Just a few of the physiological adaptations that occur subsequent to acclimation to heat include:
- Improved cardiovascular mechanisms and lower heart rate.
- Lower core body temperature during workload (surprise!)
- Higher sweat rate and earlier onset of sweating, higher sweating sensitivity as a function of increased thermoregulatory control.
- Increased blood flow to skeletal muscle (known as muscle perfusion) and other tissues.
- Reduced rate of glycogen depletion due to improved muscle perfusion (40-50% glycogen sparing).
- Increased red blood cell count (likely via erythropoietin).
- Increased efficiency of oxygen transport to muscles.
- Exposure to extreme temperatures also has a beneficial effect on mitochondrial functioning, the minute powerhouses in your cells that provide your body with the energy required to function. The key to continued energy production is to remove old and worn-out ones and generate new mitochondria, a process called biogenesis.
- Hyperthermic conditioning optimizes blood flow to the heart, skeletal muscles, skin, and other tissues because it increases the plasma volume. This causes endurance enhancements during your next workout or race when your core body temperature is elevated again.
image supplied by Absa Cape Epic, Nick Muzik
How being heat acclimated enhances endurance?
- It increases plasma volume and blood flow to the heart (stroke volume). 2,5 This results in reduced cardiovascular strain and lowers the heart rate for the same given workload. 2 These cardiovascular improvements have been shown to enhance endurance in highly trained as well as untrained athletes. 2,5,6
- It increases blood flow to the skeletal muscles, keeping them fueled with glucose, esterified fatty acids, and oxygen. The increased delivery of nutrients to muscles reduces their dependence on glycogen stores. Endurance athletes often hit a “wall” when they have depleted their muscle glycogen stores. Hyperthermic conditioning has been shown to reduce muscle glycogen use by 40%-50% compared to before heat acclimation. 3,7 This is presumably due to the increased blood flow to the muscles.
3 In addition, lactate accumulation in blood and muscle during exercise is reduced after heat acclimation. 5 3. It improves thermoregulatory control, which operates by activating the sympathetic nervous system and increasing the blood flow to the skin and, thus the sweat rate. This dissipates some of the core body heat. After acclimation, sweating occurs at a lower core temperature and the sweat rate is maintained for a longer period. 2
How to HA (Heat Acclimatize)
Passive strategies? A Sauna (passive)
Temperature? 70 -90 degrees C between 10 – 15 humidity.
How long? minimum duration of 30 min per session
How Often? minimum of 6–7 exposures on consecutive days
When? If possible, exercise bouts should be employed prior to heat sessions, jump in the sauna after a training session (with minimal delay between training and the application of heat stress, for optimal thermoregulatory-adaptive response).
When Should you start training FOR THE HEAT?
When? Start two to three weeks out from your race.
Stop? Seven days before your race to mitigate any negative impact of the heat on site.
How long will acclimatization last? Can last for upward of 10 days.
WHAT ELSE SHOULD YOU PLAN FOR?
- Once you arrive at the Absa Cape Epic, you will want to make the most of the pre-event activities and the weather, but keep a few things in mind:
- Avoid high use of air conditioning, as this can negate the effects of heat acclimation
- Increase your fluid, salt and magnesium uptake
But no matter how enthusiastic you might be, remember: Heat responsibly and with someone else, never alone. Never heat yourself while drunk, and friends don’t let friends sauna drunk. If you are pregnant or have any medical condition, saunas are not for you. Speak with your doctor before starting this or any regimen involving physical stressors.
Saunas are built to contain heat in a small area, typically elevating air temperature between 70 to 100 degrees C . Traditional Finnish saunas use dry heat with relatively low humidity, while Turkish saunas use moist heat with relatively high humidity. There are several different types of saunas from which to choose, depending on the heat source:
- Wood burning saunas — Use wood to heat rocks and the room. This produces high temperatures, and you can influence the humidity by pouring water on the rocks, or not.
- Electrically heated sauna — Rooms are high heat and low humidity, generated by an electrical heater attached to the floor of the room. Never pour water onto an electrical sauna heater.
- Infrared, near- and far-infrared saunas — Use special lamps to heat your body from the inside out, and not the entire room. Temperatures in the room are typically lower than other sauna types, but the light heats your body to a similar temperature.
- Steam rooms — Are different in that they provide high moist heat, steam and high humidity.