The Benefits of Long Runs

Pete Pfitzinger - Lab Reports - The Benefits of Long Runs

Endurance capacity and high-int... [Int J Sport Nutr Exerc Metab. 2003] - PubMed - NCBI

Endurance capacity and high-int... [Int J Sport Nutr Exerc Metab. 2003] - PubMed - NCBI

fat as fuel for endurance sports

Fat adaptation in well-trained athle... [Appl Physiol Nutr Metab. 2011] - PubMed - NCBI

7 Natural Endurance Boosters | Fitbie

7 Natural Endurance Boosters | Fitbie

Is there an optimal training intensity for enhancing the maximal oxygen uptake of distance runners?:

Midgley AW, McNaughton LR, Wilkinson M.

Department of Sport, Health and Exercise Science, University of Hull, Hull, England.

The maximal oxygen uptake (V-dotO(2max)) is considered an important physiological determinant of middle- and long-distance running performance. Little information exists in the scientific literature relating to the most effective training intensity for the enhancement of V-dotO(2max) in well trained distance runners.

Training intensities of 40-50% V-dotO(2max) can increase V-dotO(2max) substantially in untrained individuals. The minimum training intensity that elicits the enhancement of V-dotO(2max) is highly dependent on the initial V-dotO(2max), however, and well trained distance runners probably need to train at relative high percentages of V-dotO(2max) to elicit further increments.

Some authors have suggested that training at 70-80% V-dotO(2max) is optimal. Many studies have investigated the maximum amount of time runners can maintain 95-100% V-dotO(2max) with the assertion that this intensity is optimal in enhancing V-dotO(2max).

Presently, there have been no well controlled training studies to support this premise.

Myocardial morphological changes that increase maximal stroke volume, increased capillarisation of skeletal muscle, increased myoglobin concentration, and increased oxidative capacity of type II skeletal muscle fibres are adaptations associated with the enhancement of V-dotO(2max).

The strength of stimuli that elicit adaptation is exercise intensity dependent up to V-dotO(2max), indicating that training at or near V-dotO(2max) may be the most effective intensity to enhance V-dotO(2max) in well trained distance runners.

Lower training intensities may induce similar adaptation because the physiological stress can be imposed for longer periods. This is probably only true for moderately trained runners, however, because all cardiorespiratory adaptations elicited by submaximal training have probably already been elicited in distance runners competing at a relatively high level.

Well trained distance runners have been reported to reach a plateau in V-dotO(2max) enhancement; however, many studies have demonstrated that the V-dotO(2max) of well trained runners can be enhanced when training protocols known to elicit 95-100% V-dotO(2max) are included in their training programmes.

This supports the premise that high-intensity training may be effective or even necessary for well trained distance runners to enhance V-dotO(2max).

However, the efficacy of optimised protocols for enhancing V-dotO(2max) needs to be established with well controlled studies in which they are compared with protocols involving other training intensities typically used by distance runners to enhance V-dotO(2max).

1: Sports Med. 2006;36(2):117-32.

The scientific basis for high-intensity interval training: optimising training programmes and maximising performance in highly trained endurance athle

Laursen PB, Jenkins DG.

School of Human Movement Studies, University of Queensland, Brisbane, Australia. plaursen@hms.uq.edu.au

While the physiological adaptations that occur following endurance training in previously sedentary and recreationally active individuals are relatively well understood, the adaptations to training in already highly trained endurance athletes remain unclear.

While significant improvements in endurance performance and corresponding physiological markers are evident following submaximal endurance training in sedentary and recreationally active groups, an additional increase in submaximal training (i.e. volume) in highly trained individuals does not appear to further enhance either endurance performance or associated physiological variables [e.g. peak oxygen uptake (VO2peak), oxidative enzyme activity].

It seems that, for athletes who are already trained, improvements in endurance performance can be achieved only through high-intensity interval training (HIT).

The limited research which has examined changes in muscle enzyme activity in highly trained athletes, following HIT, has revealed no change in oxidative or glycolytic enzyme activity, despite significant improvements in endurance performance (p < 0.05).

Instead, an increase in skeletal muscle buffering capacity may be one mechanism responsible for an improvement in endurance performance.

Changes in plasma volume, stroke volume, as well as muscle cation pumps, myoglobin, capillary density and fibre type characteristics have yet to be investigated in response to HIT with the highly trained athlete. Information relating to HIT programme optimisation in endurance athletes is also very sparse.

Preliminary work using the velocity at which VO2max is achieved (V(max)) as the interval intensity, and fractions (50 to 75%) of the time to exhaustion at V(max) (T(max)) as the interval duration has been successful in eliciting improvements in performance in long-distance runners.

However, V(max) and T(max) have not been used with cyclists. Instead, HIT programme optimisation research in cyclists has revealed that repeated supramaximal sprinting may be equally effective as more traditional HIT programmes for eliciting improvements in endurance performance.

Further examination of the biochemical and physiological adaptations which accompany different HIT programmes, as well as investigation into the optimal HIT programme for eliciting performance enhancements in highly trained athletes is required.

1: Sports Med. 2002;32(1):53-73.

Impact of resistance training on endurance performance. A new form of cross-training?

In accordance with the principles of training specificity, resistance and endurance training induce distinct muscular adaptations.

Endurance training, for example, decreases the activity of the glycolytic enzymes, but increases intramuscular substrate stores, oxidative enzyme activities, and capillary, as well as mitochondrial, density.

In contrast, resistance or strength training reduces mitochondrial density, while marginally impacting capillary density, metabolic enzyme activities and intramuscular substrate stores (except muscle glycogen).

The training modalities do induce one common muscular adaptation: they transform type IIb myofibres into IIa myofibres. This transformation is coupled with opposite changes in fibre size (resistance training increases, and endurance training decreases, fibre size), and, in general, myofibre contractile properties.

As a result of these distinct muscular adaptations, endurance training facilitates aerobic processes, whereas resistance training increases muscular strength and anaerobic power.

Exercise performance data do not fit this paradigm, however, as they indicate that resistance training or the addition of resistance training to an ongoing endurance exercise regimen, including running or cycling, increases both short and long term endurance capacity in sedentary and trained individuals.

Resistance training also appears to improve lactate threshold in untrained individuals during cycling. These improvements may be linked to the capacity of resistance training to alter myofibre size and contractile properties, adaptations that may increase muscular force production.

In contrast to running and cycling, traditional dry land resistance training or combined swim and resistance training does not appear to enhance swimming performance in untrained individuals or competitive swimmers, despite substantially increasing upper body strength.

Combined swim and swim-specific 'in-water' resistance training programmes, however, increase a competitive swimmer's velocity over distances up to 200 m.

Traditional resistance training may be a valuable adjunct to the exercise programmes followed by endurance runners or cyclists, but not swimmers; these latter athletes need more specific forms of resistance training to realise performance improvement.

1: Sports Med. 1998 Mar;25(3):191-200.

Aerobic High-Intensity Intervals Improve VO2max More Than Moderate Training

Aerobic High-Intensity Intervals Improve VO2max More Than Moderate Training.

Medicine & Science in Sports & Exercise. 39(4):665-671, April 2007.

JAN HELGERUD; KJETILL HØYDAL; EIVIND WANG; TRINE KARLSEN; PÅLR BERG; MARIUS BJERKAAS; THOMAS SIMONSEN; CECILIES HELGESEN; NINAL HJORTH; RAGNHILD BACH; JAN HOFF

Abstract:

Purpose:

The present study compared the effects of aerobic endurance training at different intensities and with different methods matched for total work and frequency. Responses in maximal oxygen uptake (VO2max), stroke volume of the heart (SV), blood volume, lactate threshold (LT), and running economy (CR) were examined.

Methods:

Forty healthy, nonsmoking, moderately trained male subjects were randomly assigned to one of four groups:

1) long slow distance (70% maximal heart rate; HRmax);

2) lactate threshold (85% HRmax);

3) 15/15 interval running (15 s of running at 90-95% HRmax followed by 15 s of active resting at 70% HRmax);

4) 4 x 4 min of interval running (4 min of running at 90-95% HRmax followed by 3 min of active resting at 70%HRmax).

All four training protocols resulted in similar total oxygen consumption and were performed 3 dwk-1 for 8 wk.

Results:

High-intensity aerobic interval training resulted in significantly increased VO2max compared with long slow distance and lactate-threshold training intensities (P <>

The percentage increases for the 15/15 and 4 x 4 min groups were 5.5 and 7.2%, respectively, reflecting increases in VO2max from 60.5 to 64.4 mLkg-1min-1 and 55.5 to 60.4 mLkg-1min-1.

SV increased significantly by approximately 10% after interval training (P < 0.05).

Conclusions:

High-aerobic intensity endurance interval training is significantly more effective than performing the same total work at either lactate threshold or at 70% HRmax, in improving VO2max. The changes in VO2max correspond with changes in SV, indicating a close link between the two.

(C) 2007 The American College of Sports Medicine