STRENGTH FOR ENDURANCE
How Increasing Strength also Improves Endurance
BY MARK TWIGHT
Certain physiological and biomechanical adaptations only result from proper strength training - they cannot be achieved any other way. Endurance athletes often avoid real strength training due to the belief that such efforts will make them bigger and tighter and slower. The exact opposite is true (contingent on proper execution).
Along with increased peak force and rate of force production the intelligent use of strength training can cause the following physiological gains:
Improved muscle capillarization
Increased fuel availability (to the muscle)
Improved muscular endurance (due to increase in size/efficiency of mitochondria)
Stronger bones
Stronger connective tissue
Better flexibility
Improved neuromuscular coordination
Reduced fatigue in the arms and postural muscles
Improved movement economy
Reduced risk of injury
None of these benefits are contradictory to endurance performance. Perhaps the most important gains may be realized by strengthening the hands, wrists, and arms. Once these peripheral muscles tire during effort (perhaps from carrying a weapon) the muscles further up the chain - closer to the core - become engaged to support them. As the shoulder tires, posture suffers and the diaphragm is compressed, which reduces O2 uptake efficiency. As these postural changes reduce movement economy the oxygen cost increases because more, larger muscles are recruited in an attempt to maintain the posture required for efficient respiration. Also, stronger legs are more mechanically efficient, which reduces the overall oxygen cost of locomotion.
Blitz reviewing breakfast after a strength session towing the BFS sled and carrying the 100-pound bag affectionately known as "Judy"
Strength training can also reduce muscle imbalances that often lead to injury, and having strong feet, legs, hips and core can reduce the strain on the spine. Since the trend is to use lighter, less supportive footwear in the field it is wise to improve foot strength. This may be done by executing the Olympic lifts or certain Kettlebell movements without shoes and running barefoot once or twice per month (on a soft surface of course).
At Gym Jones we don't consider that any training activity is necessarily specific to any particular outcome. In accord with this idea we switch-up modalities, often using sprint training to improve strength and weights or gymnastic movements to improve cardiovascular fitness. The point being that strength training to increase endurance does not necessarily take place in the weight room.
We run with ski poles to increase the oxygen demands (since more muscles are engaged in the work). We run towing a weighted sprint sled to train explosive strength, and because the movements are the same as those used during locomotion at any speed the strength increases are fairly specific and neuromuscularly correct.
Full squat movements executed at high heart and respiratory rates have been shown to increase diaphragm strength and endurance due to the externally induced stretching and compressing of that muscle. The more endurance the diaphragm has the longer efficient respiration cycles may be maintained during effort. A typical movement that causes this adaptation would be Wall Ball (medicine ball thrown at a ten foot-high target starting from the front squat position) or Thruster (front squat to overhead press). Movements should be executed for repetitions; try a set of 15 Tabata Thrusters (20 seconds of work followed by ten seconds of rest repeated 15 times) with a barbell weighing 65-95 pounds. Apart from the crazy metabolic stress, the big, compound movement will also cause a strong neuro-endocrine response as well as muscular adaptations that improve strength.
Another favorite combination is the 400-meter Lunge + Overhead Press. Start with a 45# barbell held in any position, take five lunges forward, stop, stand, clean the bar and execute five overhead presses. Repeat for 400 meters. It will take approximately 20-30 minutes and feature heart rates in the 160-170 range. The lunge improves leg strength and coordination while the overhead press improves core, shoulder and arm strength - and endurance. Carrying the bar loads the skeletal and core muscles, compressing the diaphragm and costal muscles, which stimulates an increased ventilatory drive (breathing in with more force to counteract the resistance of the load).
Because all movement is initiated by the core and finished by the extremities any increase in core strength improves all movement efficiency. Different coaches follow similar formulas; my Olympic lifting coach Dan John used to train with a throwing coach (discus) who wouldn't teach athletes technical throwing motions until they could overhead squat bodyweight for 15 reps. The underlying thesis is that putting weight overhead is one of the best methods of improving core strength. Dan himself believes that a double bodyweight deadlift indicates a foundation solid enough to begin meaningful training. The DL and its derivatives - C&J, snatch, various KB/DB swings and movements, the squat and its variants, - all contribute to great posterior strength. Anterior strength may be developed by training the front lever, L-sit, planks, ring push-ups, throwing a medicine ball at a ten foot-high target from the Glute Ham Developer, and other medicine ball partner drills.
Fundamental strength drills, executed in a manner that improves recruitment rather than increasing mass, and combined with a diet that fuels the effort and recovery but does not increase mass is as important as metabolic conditioning to the endurance athlete. Building power from that strength is the subject of the paper titled "The Holy Grail in Speed Training" describing the experience coach Barry Ross had with Allyson Felix. This work is based on research conducted by Harvard Medical School research physiologist Peter Weyand into the idea of mass-specific force. His thesis corresponds exactly to the concept of Relative Strength we revere at Gym Jones where having the greatest power-to-weight ratio has positive benefits for many athletic challenges.