Snow Bowl Ride in Flagstaff Arizona

I had a great ride between swim training sessions yesterday. For those who are interested here is the route that physiologist Rob Rupf and I did:

The altitude here is about 7000 ft and there was 800 m of climbing to get to the top of the route (sorry about the mix of imperial and metric units there...). Here is the garmin file with heart rate and elevation.

Here are a few pics from the ride:

 

And finally - if anyone is interested in more information on altitude training here is a short article on the topic:

Hypoxic training is a practice where athletes train at varying elevations above sea level in order to take advantage of possible physiological effects on the human body.  Exercise and living in hypoxia may have a significant influence on the oxygen transport and utilization.  It has been hypothesized that these metabolic and musculo-cardio-respiratory responses would be of benefit to athletes as they appear to be similar to the changes bought about by endurance training. 

The physiological adaptations to exposure to altitude and/or hypoxia are varied and complex.  The literature that has been reviewed in Wells (1998) suggests the following:

The physiological changes that these authors have suggested occur with altitude training are:

Weil et al. (1967) suggests that an optimal altitude for training may correspond with a PO2 of 135mmHg, an oxygen saturation of 92% and roughly 2200-2500m above sea level.  The altitude of 2200-2500m proposed by Weil et al. was later supported by Inger et al. (1992).  Inger et al. showed that three weeks of altitude training at 1900m by elite cross country skiers resulted in an increase in hemoglobin concentration of 5% an a decreased blood lactate concentration in a standardized sub-maximal exercise test with no decrement in VO2 max. 

The limited information that is available suggests that the longer the duration of the hypoxic stimulus, the greater the erythropoietic response and associated hematological adaptation (Schmidt et al., 1993), specifically an increase in hemoglobin concentration of 1% per week independent of hemoconcentration.  Thus, the hypothesis that, if detraining can be avoided, the longer the athlete can stay at altitude, the greater the physiological benefits for training and performance.

Recently, Rusko (1996) presented data from studies on Scandinavian endurance athletes who have benefited from a “train at sea level and live in hypoxia” program.  Results from these studies on six cross country skiers that spent 16 hours a day in an hypoxia house showed that serum erythropoeitin and reticulocyte (new red blood cells) numbers were significantly increased after 8 days.  These variables have been shown to stay elevated for up to 2 weeks when athletes were exposed to hypoxia house conditions. Red blood cell volumes were increased by 7% (non-significant increase) over a normoxic control group after a 4 week training regimen that included 14-16 hours a day in the altitude house.  Nummela et al. (1996) found that 10 days of training and exposure to hypoxia in an altitude house resulted in increased 400m running velocity, running velocity at exhaustion, velocity at a lactate level of 5mM, as well as increased pH and HCO₃ concentrations at rest in 6 subjects over 6 control subjects who performed the same training protocols but were not exposed to hypoxic conditions.  More recently, Levine and Stray-Gundersson (1997) tested their train low live high hypothesis on 39 competitive runners who were randomized into three groups.  A live high train low (high-low) group, a live and train high group (high-high) group and a group that lived and trained at sea level (low-low).  The hypoxic exposure was preceded by a 6 weeks of sea level training to ensure that all subjects had reached a plateau and were similar in conditioning.  The results indicated that both hypoxic groups improved VO₂max by 5% and red blood cell mass volume by 9%, neither of which changed in the control group.  The 5 km run time was only improved in the high-low group, as did the velocity at VO₂max, and at ventilatory threshold.  These authors concluded that four weeks of living high-training low improves sea level performance in trained runners due to hypoxic acclimatization and maintenance of sea-level training velocities.

Summary

Briefly, altitude acclimatization has many physiological effects that may impact athletic performance.  Positive acclimatizations may include increased blood hemoglobin, increased buffer capacity, and improvements in skeletal muscle function. Decrements in performance may occur due to decreased cardiac output, decreased skeletal muscle blood flow, decreased maximal aerobic power, increased hemolysis, increases in sympathetically mediated glycogen depletion and problems with immune function (Bailey, 1997).  Constant moderate altitude training has not been demonstrated to improve sea level performance, however, the newer technique of live-high train-low may show some promise for eliciting the desired physiological improvements while concurrently allowing athletes to maintain training volume and intensity.  The field of altitude physiology and investigations into training at altitude is an area with great potential for enhancing our understanding of how the human body reacts to extreme environments and warrants additional research to answer the questions that have been raised in this paper.

References

Bailey, D.M., Davies, B. (1997). Physiological implications of altitude training for endurance performance at sea level: a review. British Journal of Sports Medicine, 31: 183-190.

Ingjer, F., Myhre, K. (1992). Physiological effects of altitude training on elite male cross-country skiers. Journal of Sport Science, 10, 37-47.

Levine, B.D., Stray-Gundersen, J. (1997). “Living-high – training low”: effect of moderate-altitude acclimatization with low-altitude training on performance.  Journal of Applied Physiology, 83(1): 102-112.

Nummela, A., Jouste, P., Ruske, H.K. (?). Effect of living high and training low on sea level anaerobic performance in runners.  Medicine and Science in Sports and Exercise, S124.

Rusko, H.R. (1996). New Aspects of Altitude Training. American Journal of Sports Medicine, 24(6): S48-S52.

Schmidt, W., Spielvogel, H., Eckardt, U., Quintela, A., Penaloza, R. (1993). Effects of chronic hypoxia and exercise in plasma erythropoetin in high altitude residents.  Journal of Applied Physiology, 74(4): 1874-1878. 

Weil , J.V., Jamieson, G., Brown, D.W. (1967). The red cell mass-arterial oxygen relationship in normal man.  Journal of Clinical Investigation, 47, 1627-39.