Blog 3 (How We Get Stronger)
How We Get Stronger
Increases in strength come from many factors: Hypertrophy, Neural, and increased energy substrate storage.
Hypertrophy is an increase in the size of the muscle. Muscles are made up of individual fibres which are of three types:
Type I, AKA: Slow twitch, or slow oxidative glycolytic. These are the endurance fibres; they don't enlarge in response to exercise to the same degree as Fast twitch fibres, but they are very fatigue resistant. These fibres are recruited first.
Type IIa, AKA: Fast twitch A, or fast oxidative glycolytic. As the load increases these fibres are recruited. They are moderately fatigue resistant and enlarge in response to training giving them greater force producing capability.
Type IIb, AKA: Fast twitch B, or fast glycolytic. These are the hardest fibres to recruit, as they are recruited last only under the heaviest loads. They have poor endurance, but enlarge in response to training and so have high force producing potential.
Hypertrophy is generally linked with exercise using moderately high weights; around 75% of the maximum weight you can lift once (your MVC Maximum Voluntary Contraction), and medium repetitions; 6-12 reps for 3 sets or more.
For isometric exercise the ideal load and duration is less clear, but the presence of fatigue metabolites appears to be a useful marker, so longer durations with short rests that only allow for partial recovery, and moderately high loads.
A further complication of isometric exercise is the specificity of the joint angle at which you train. Strength gained at one angle will only transfer weakly to other angles. For the fingers this is further complicated because each finger is multi joint, so there is more than one muscle involved, each contributing to a different degree depending on the grip used. For this reason training open handed will not transfer to the crimp grip. If you want to get stronger on crimps you have to train on crimps.
Neural factors are the minds influence over the muscles and individual muscle fibres. These include:
The ability to contract large numbers of muscle fibres simultaneously. The maximum number of muscle fibres we can contract simultaneously defines the maximum force produced by the muscle, this is limited to prevent damage to the tendon and bone. Tiny tension sensing receptors located in tendons called Golgi Tendon Organs (GTO's) provide feedback about the degree of tension in the tendon, and can inhibit contraction of the muscle to reduce it and prevent damage. With regular training using high loads the threshold at which the GTO's start to inhibit muscle contraction can be raised, allowing greater recruitment and higher force to be developed.
In simple movement like a bicep curl the bicep contracts to raise the forearm, whilst the triceps on the back of the arm must lengthen. In this movement the bicep is referred to as the Agonist as it is causing the movement, and the tricep is the Antagonist as it is opposing the movement.
When the agonist contracts against a load the antagonist also contracts to a lesser degree, this can provide braking to protect the joint in the case of rapid movements like throwing; the tricep (the agonist in this case) contracts rapidly to extend the arm, whilst the antagonist (bicep) contracts to slow the movement at the end and prevent the arm from hyper-extending and damaging the joint and the antagonist.
Antagonists also contract in response to high tension sensed by the GTO's in the agonist tendon, to inhibit the action of the agonist and prevent further contraction and possible damage.
One of the effects of strength training with high loads is decreased co-contraction of the antagonists leading to increased agonist force output. This is one of the major reasons isometric strength gains are so angle specific; the more you train at a specific joint angle the less the antagonist co-contraction there is at that angle.
Because neural training involves the heaviest loads its potential for injury is the highest; a thorough warm-up is essential, and you should only train when you feel totally fresh and recovered, the amount of volume done in a session should be low, but the intensity should be high.
You should never go to failure; neural training is all about building on success.
Energy Substrate Storage.
Strength training increases the intra muscular stores of the substrates that the muscle uses for energy such as Adenosine Tri Phosphate, Creatine Phosphate and Glycogen.
Hormonal Responses to Training
Heavy resistance training causes the release of hormones into the blood which stimulate hypertrophy in muscles. The greater the muscle mass which is stressed by exercise the greater the hormonal response. A study was conducted where one group performed bicep curls whilst another group performed 2 exercises: bicep curls and leg presses. The group that combined bicep curls and leg presses showed a greater increase in bicep strength than the group that performed only bicep curls. This was attributed to the greater hormonal response caused by the larger muscle mass exercised. Combining a workout for the fingers/forearm, which has a very small muscle mass, with other workouts that use larger muscles may elicit a greater hormone release and lead to stronger fingers, just watch you don't get big heavy legs.