A Report of the First Annual USOC-ACSM Human Performance Summit 

Gordon Sleivert, PhD, Director, Human Performance Center, School of Physical Education, University of Otago, Dunedin, New Zealand. 
Sportscience News Sep-Oct 1997 

The topic of this panel discussion was preparation for events lasting 1-5 minutes, a mystery zone requiring aerobic and anaerobic power. Most panelists agreed that: aerobic development is of primary importance; aerobic and anaerobic fitness should be maintained in all phases of training; a prolonged period of anaerobic training increases the risk of overstraining; shorter events require more resistance training, which should emphasize development of relative strength or power rather than muscle hypertrophy; and to taper for a competition, maintain high-intensity training while reducing training volume. 

800-m runner
 Wilson Kipketer 
In June this year I attended a one-day "summit" with the title of Training and Competing in the Mystery Zone. The summit, a panel discussion between invited speakers, was held in Denver straight after the annual meeting of the American College of Sports Medicine. It was the first in an annual series of summits on human performance, organized jointly by the US Olympic Committee and ACSM. A number of prominent sport scientists and elite-level coaches based in the US were on the panel. The international sports science community was also well represented.

Events that take between one and five minutes to complete require energy from both the aerobic and oxygen-independent (anaerobic) systems. Some coaches have described this competition range as the mystery zone, because strategies for training and competing in events within this zone are not well understood. The goal of the meeting was to provide a consensus statement about training and competing in the mystery zone, for use by US athletes, coaches, and sport scientists. The discussion covered other topics, such as the coach-scientist relationship, the use of sportscience by high performance sport, and the gap between sport and the scientist. I will restrict this report to training for events in the mystery zone. Pacing and other strategies for competition in the mystery zone were not discussed.

Energy Supply

It is now acknowledged that energy supply for these events is approximately 50% aerobic and 50% anaerobic at the one-minute end of the spectrum. The anaerobic contribution is a mixture of alactic energy supply and oxygen independent glycolysis. When ATP is utilized at high rates in the first 10-15 seconds of exercise it is primarily regenerated by the ATP-CP system which does not generate lactate as a by-product. This system is therefore often referred to as the "alactic system". Simultaneously glycolysis is generating ATP and lactate is being produced. This "lactate" system cannot supply ATP as quickly as the alactic system but can sustain energy supply for up to 60 s, or even a bit longer at a rate faster than the aerobic glycolytic system. As the events get closer to five minutes, the importance of the aerobic system increases. You must therefore train both aerobic and anaerobic energy systems to be successful in the mystery zone.

Aerobic Training

It is well known that aerobic zone training develops the ability of the muscles to utilize oxygen and provide energy during exercise. The experts agree that this type of training, also known as base training, also enhances the "VO2 kinetics" the rate athletes recruit the aerobic system at the start of the event. This enhancement is important, because an increase in the rate that the aerobic system kicks in at the start of exercise will save anaerobic capacity for the end of the event and thereby help maintain pace or intensity. Base training improves kinetics by increasing the density of energy-producing mitochondria within muscle. Base training also increases the density of capillaries, which deliver oxygen to the muscle and remove substances that cause fatigue. The experts also speculated that large volumes of aerobic training may develop the ability of muscle and nerve to maintain sodium and potassium homeostasis during exercise, another factor thought to be linked to fatigue. But more research is required, since it was not clear whether interval training is any less effective in modifying any of these factors.

Anaerobic Training

High-intensity training or anaerobic training develops the ability of muscle and blood to buffer and tolerate high levels of lactic acid and other waste products. The activity of key enzymes important to anaerobic energy supply is also increased with high intensity training. The experts all agreed that anaerobic capacity can be increased through this type of training and that it is an integral part of preparation for mystery zone events.

Balancing Aerobic and Anaerobic Training

The debate continues regarding the relative importance of developing an aerobic base prior to inserting significant amounts of anaerobic training. All of the coaches present agreed that base development was essential, and all utilized large volumes of aerobic training for the majority of the training year. How much base training is optimal? The US swim coaches suggested 95% of training volume should be aerobic, while US cycling scientist, Dr Ed Burke, suggested 50% of training should be aerobic for events of one- to two-minutes duration. There was no consensus in this area.

Mixing Training Types

There was agreement that too much base training can be detrimental, and it seems to be important to train other energy systems simultaneously with the aerobic system. As an example, Olympic gold medalist Dr Peter Snell pointed out that in his best world record year he maintained his speed training during four months of base training immediately after the European track season. The US swim coach even suggested that the alactic energy system could be trained every day. It was agreed that alactic training should occur early in a workout and that other anaerobic training should not be intermingled with aerobic training within a single session. The experts also pointed out that frequent anaerobic lactic acid training may lead to exhaustion and even overstraining as a result of the muscle damage from the acidity or other metabolic waste products. Twice a week was suggested as a guideline for training the lactate system, but many coaches and trainers use much higher frequencies. For example, the Australian track cycling team often inserts twice-a-day anaerobic track workouts on two consecutive days within anaerobic training cycles, and reportedly obtain good results. The optimal training frequency for training the lactic acid system is therefore not clear, but everyone agreed that prolonged periods of anaerobic training is hazardous to the health of the athlete and put many athletes at risk of overstraining.

The maintenance of aerobic fitness during anaerobic training was also identified as being a critical factor in the mystery zone. At least several aerobic workouts should be inserted each week during periods of anaerobic training emphasis. We also know that interval-type anaerobic training provides some maintenance of aerobic function, so there is no need to get carried away with aerobic maintenance training.

The issue of how to structure training was not discussed: it appeared to be assumed that everybody periodizes their training. In my opinion, the evidence that periodization is the best way to structure training is purely anecdotal. Sebastian Coeâs father and coach, Peter Coe, along with sports scientist David Martin, have suggested that part of Coeâs middle distance success story was due to his "multi-paced" training strategy. With this strategy, each of the components important to competition was trained all year round, the rationale being that athletes should never lose touch with any of the important performance factors. Greater emphasis was placed on base work during the preparation phase and speed work during the pre-competition and competition phases, but no training mode was ever abandoned. As with traditional periodized training, there is scant scientific evidence to support Coe's method. Coaches must decide for themselves which approach best meets their athletes' needs. Until there is more evidence, I feel that a balance is the safest bet.

Strength Training in the Mystery Zone

The role of strength training for mystery-zone events was only briefly discussed. Support was expressed by most scientists and coaches for a role of strength training in the short duration events. In particular it was emphasized that strength training for this event range should be more event specific than the standard hypertrophy-based training. That is, training should be aimed at developing muscular power and/or relative strength.. The American swim coach suggested that strength training should be prescribed to match race strategy and was more important for swimmers with long verses short distances per stroke. Dr Ed Burke pointed out that plyometric training was useful only in cycling for events up to one kilometer distance (about one minute). Robert Vaughan reiterated this point from an athletics perspective, stating that the importance of strength training diminished on the track as race distance increased. This may be true, but resistance training should not be dismissed as worthless for the longer events, as recent evidence from both Finland and the US suggests that strength training can improve performance in races up to 10 km in well trained runners. The possible importance of strength training as a method of injury prevention should also not be overlooked.

Tapering and Peaking for the Mystery Zone

Is peaking different for the mystery zone? It was generally agreed that most athletes competing in the mystery zone have to peak less frequently than endurance athletes. It was also agreed that you can maintain a peak for longer when training for shorter anaerobic events, for example the track 400 meters, versus longer aerobic events. Both the coach and athlete must balance regeneration with maintenance, because many factors that improve with training are lost quickly. The US rowing coach outlined a typical taper for his athletes. Most of their tapering involves three weeks of high intensity training, decreasing volume by up to 40%, with intensity set at 95% to 105% of race pace. Many variations of taper are utilized for peaking in the mystery zone, and no consensus was reached between any of the experts.


As you have probably decided by now, training and competing in the mystery zone is a mystery zone in itself. The experts can't agree on the best strategies. I hope this article stimulates you to think about your own training strategies for the mystery zone and helps you compare your training philosophies with those of other coaches and sport scientists. 

Edited by Will Hopkins. Webmastered by Alfred Zommers. Last updated 07 August 1997 · · Homepage · Copyright ©1997