Balanced strength

5 Trainable Qualities of Strength

Study

A group of researchers recently put out an article with updated strength classification systems and broke them down into 5 trainable qualities.  The qualities described are 1. Fast Maximal Dynamic Strength, 2. Heavy Maximal Dynamic Strength, 3. Maximal Isometric Strength,  4. Explosive Strength and 5. Reactive Strength. Below is a description of each quality as well as examples for their application.  It is important to note that these qualities are best trained using multi joint movements and that training all of these qualities in a systematic manner can help minimize strength deficits, reduce injury risks and lead to more consistent progress.  

Fast Maximal Dynamic Strength

The maximum force that can be produced over somewhat quick movement times against little to no additional load and is usually trained around 20-40% of someone’s one rep max. Examples: plyometric activities, ballistic kettlebell movements, explosive bodyweight or light externally loaded exercises (exercises only count if one has a 30+ rep max for a given movement)

Heavy Maximal Dynamic Strength 

The maximum amount of weight someone can lift and is trained best between 75-90% of someone's 1 rep max (the equivalent of a 3-8 rep max). Examples: any exercise that can be loaded to an extent where 8 reps or less would be able to be achieved such as squats, deadlifts, lunges, presses, pulls and rows.

Maximal Isometric Strength

Trained very similarly to heavy maximal dynamic strength but involves pausing in a key body position of a specific lift for 2-5 seconds, producing similar strength results, emphasizing strengthening sticking points, and potentially minimizing injury risk. Examples: pause squats, pause deadlifts, pause pull ups and pause presses.

Explosive Strength 

The measure of early stage force production in the first 0.15 seconds of a repetition or the ability to recruit fibers fast which is important because most athletic movements only last 0.1-0.2 seconds. Examples: any exercise that can be initiated hard and fast and externally loaded (bodyweight and plyometrics won’t cut it) such as squats, deadlifts, lunges, presses, pulls and rows.

Reactive Strength

Classified as the ability to use a muscle’s reflex and is an important ability for an athlete to tolerate movements with a strong eccentric component (muscle lengthening phase).  Examples: running sprints, plyometric and agility drills, kettlebell swings, and speed weightlifting where multiple reps and a rapid change in direction, without setting the weight down, are present.

Source

James et al. “Strength Classification and Diagnosis: Not All Strength is Created Equal.” Strength and Conditioning Journal, Vol. 45, Issue 3, June 2023, pp.333-341, DOI: 10.1519/SSC.0000000000000744