27. ALTITUDE + HEAT TRAINING SEQUENTIAL COMBO OPTIMIZES HB-MASS RESPONSE!

Photo by Mateusz Suski on Unsplash

Altitude training camps are a very common method to enhance aerobic physiological adaptations for endurance performance. Why? the lower partial pressure of oxygen (hypoxic stimulus) at high altitude increases erythropoietin production, which in turn stimulates an increase in haemoglobin mass (HB-mass). As haemoglobin is the oxygen blood transporter, an increase in HB-mass permits more oxygen to arrive at working muscle and so to increase performance.

Altitude training camps are usually performed 2-4 weeks before the goal race. In this way it is believed to race with the altitude’s HB-mass gains while having recovered from the (usually) high training load performed during the camp. However, unfortunately Hb-mass gains are already lost within 10-25 days weeks after removal of the hypoxic stimulus and this makes not always sure that we are racing both in a fully recovered state and with the maximum HB-mass benefits obtained through the altitude camp.

So, finding a way to prevent the rapid loss of HB-mass after altitude training camps can be very important to optimise race performance.

In a previous research summary, we saw that also heat training stimulates an increase in HB-mass. In another research summary, we learned that heat training positive adaptations can be replicated with a cheap and practical solution: wearing additional clothes during indoor training sessions (heat suit training).

Does 3x week heat suit training sessions after altitude training camps permit to maintain the HB-mass increase obtained during the altitude camp?

A hot of the press study published in August 2024 by Bent Rønnestad and Colleagues (Inland Norway University of Applied Science, Lillehammer, Norway) on Medicine & Science in Sports & Exercise tried to answer this question.

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HOW DID THEY TRAIN?

• They recruited 18 male elite cyclists (mean VO2max: 76).

• They all performed a 3-weeks altitude training camp sleeping at ~2100m a.s.l. (Trepalle, Livigno, Italy) and training between 1800-2200m. So, the approach was live high-train high.

• After finishing the altitude training camp, cyclists were divided into two groups (HEAT vs CONTROL) which performed for 3.5 weeks the same training program with the only following difference:

  • HEAT GROUP: performed 3xweeks 50min indoor heat suit training sessions (see details below).

  • CONTROL GROUP: didn’t perform any heat training sessions.

• Training volume and time spent in zones were similar between groups.

  Total volume:

  • Before altitude: ~13h per week

  • During altitude ~16h per week

  • After altitude ~13h per week

• Heat suit training sessions details:

  • Environmental conditions: afternoon, indoor, ⁓20°C environmental temperature.

  • Additional clothes worn to limit heat loss: upper and lower body wool layer, wool hat, down jacket, nylon rain jacket, and nylon pants.

  • Intensity: power output was set to reach a rectal temperature of ~38.5°C and a fluid loss ≥1.5 L measured 1–3 min after each session. This resulted in an 126 W average power output, which is very likely zone 1 in a 5/7 zones model for these cyclists: very low!

• Iron supplementation: all participants ingested 100mg of Nycoplus Ferro-Retard

  from two weeks before starting the altitude camp until 3.5 weeks after the altitude camp when the last test of the study was completed. This because iron levels are important to permit an increase in haemoglobin mass.

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